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class http.server.CGIHTTPRequestHandler(request, client_address, server)
This class is used to serve either files or output of CGI scripts from the current directory and below. Note that mapping HTTP hierarchic structure to local directory structure is exactly as in SimpleHTTPRequestHandler. Note CGI scripts run by the CGIHTTPRequestHandler class cannot execute redirects (HTTP code 302), because code 200 (script output follows) is sent prior to execution of the CGI script. This pre-empts the status code. The class will however, run the CGI script, instead of serving it as a file, if it guesses it to be a CGI script. Only directory-based CGI are used — the other common server configuration is to treat special extensions as denoting CGI scripts. The do_GET() and do_HEAD() functions are modified to run CGI scripts and serve the output, instead of serving files, if the request leads to somewhere below the cgi_directories path. The CGIHTTPRequestHandler defines the following data member:
cgi_directories
This defaults to ['/cgi-bin', '/htbin'] and describes directories to treat as containing CGI scripts.
The CGIHTTPRequestHandler defines the following method:
do_POST()
This method serves the 'POST' request type, only allowed for CGI scripts. Error 501, “Can only POST to CGI scripts”, is output when trying to POST to a non-CGI url.
Note that CGI scripts will be run with UID of user nobody, for security reasons. Problems with the CGI script will be translated to error 403. | python.library.http.server#http.server.CGIHTTPRequestHandler |
cgi_directories
This defaults to ['/cgi-bin', '/htbin'] and describes directories to treat as containing CGI scripts. | python.library.http.server#http.server.CGIHTTPRequestHandler.cgi_directories |
do_POST()
This method serves the 'POST' request type, only allowed for CGI scripts. Error 501, “Can only POST to CGI scripts”, is output when trying to POST to a non-CGI url. | python.library.http.server#http.server.CGIHTTPRequestHandler.do_POST |
class http.server.HTTPServer(server_address, RequestHandlerClass)
This class builds on the TCPServer class by storing the server address as instance variables named server_name and server_port. The server is accessible by the handler, typically through the handler’s server instance variable. | python.library.http.server#http.server.HTTPServer |
class http.server.SimpleHTTPRequestHandler(request, client_address, server, directory=None)
This class serves files from the current directory and below, directly mapping the directory structure to HTTP requests. A lot of the work, such as parsing the request, is done by the base class BaseHTTPRequestHandler. This class implements the do_GET() and do_HEAD() functions. The following are defined as class-level attributes of SimpleHTTPRequestHandler:
server_version
This will be "SimpleHTTP/" + __version__, where __version__ is defined at the module level.
extensions_map
A dictionary mapping suffixes into MIME types, contains custom overrides for the default system mappings. The mapping is used case-insensitively, and so should contain only lower-cased keys. Changed in version 3.9: This dictionary is no longer filled with the default system mappings, but only contains overrides.
directory
If not specified, the directory to serve is the current working directory. Changed in version 3.9: Accepts a path-like object.
The SimpleHTTPRequestHandler class defines the following methods:
do_HEAD()
This method serves the 'HEAD' request type: it sends the headers it would send for the equivalent GET request. See the do_GET() method for a more complete explanation of the possible headers.
do_GET()
The request is mapped to a local file by interpreting the request as a path relative to the current working directory. If the request was mapped to a directory, the directory is checked for a file named index.html or index.htm (in that order). If found, the file’s contents are returned; otherwise a directory listing is generated by calling the list_directory() method. This method uses os.listdir() to scan the directory, and returns a 404 error response if the listdir() fails. If the request was mapped to a file, it is opened. Any OSError exception in opening the requested file is mapped to a 404, 'File not found' error. If there was a 'If-Modified-Since' header in the request, and the file was not modified after this time, a 304, 'Not Modified' response is sent. Otherwise, the content type is guessed by calling the guess_type() method, which in turn uses the extensions_map variable, and the file contents are returned. A 'Content-type:' header with the guessed content type is output, followed by a 'Content-Length:' header with the file’s size and a 'Last-Modified:' header with the file’s modification time. Then follows a blank line signifying the end of the headers, and then the contents of the file are output. If the file’s MIME type starts with text/ the file is opened in text mode; otherwise binary mode is used. For example usage, see the implementation of the test() function invocation in the http.server module. Changed in version 3.7: Support of the 'If-Modified-Since' header. | python.library.http.server#http.server.SimpleHTTPRequestHandler |
directory
If not specified, the directory to serve is the current working directory. Changed in version 3.9: Accepts a path-like object. | python.library.http.server#http.server.SimpleHTTPRequestHandler.directory |
do_GET()
The request is mapped to a local file by interpreting the request as a path relative to the current working directory. If the request was mapped to a directory, the directory is checked for a file named index.html or index.htm (in that order). If found, the file’s contents are returned; otherwise a directory listing is generated by calling the list_directory() method. This method uses os.listdir() to scan the directory, and returns a 404 error response if the listdir() fails. If the request was mapped to a file, it is opened. Any OSError exception in opening the requested file is mapped to a 404, 'File not found' error. If there was a 'If-Modified-Since' header in the request, and the file was not modified after this time, a 304, 'Not Modified' response is sent. Otherwise, the content type is guessed by calling the guess_type() method, which in turn uses the extensions_map variable, and the file contents are returned. A 'Content-type:' header with the guessed content type is output, followed by a 'Content-Length:' header with the file’s size and a 'Last-Modified:' header with the file’s modification time. Then follows a blank line signifying the end of the headers, and then the contents of the file are output. If the file’s MIME type starts with text/ the file is opened in text mode; otherwise binary mode is used. For example usage, see the implementation of the test() function invocation in the http.server module. Changed in version 3.7: Support of the 'If-Modified-Since' header. | python.library.http.server#http.server.SimpleHTTPRequestHandler.do_GET |
do_HEAD()
This method serves the 'HEAD' request type: it sends the headers it would send for the equivalent GET request. See the do_GET() method for a more complete explanation of the possible headers. | python.library.http.server#http.server.SimpleHTTPRequestHandler.do_HEAD |
extensions_map
A dictionary mapping suffixes into MIME types, contains custom overrides for the default system mappings. The mapping is used case-insensitively, and so should contain only lower-cased keys. Changed in version 3.9: This dictionary is no longer filled with the default system mappings, but only contains overrides. | python.library.http.server#http.server.SimpleHTTPRequestHandler.extensions_map |
server_version
This will be "SimpleHTTP/" + __version__, where __version__ is defined at the module level. | python.library.http.server#http.server.SimpleHTTPRequestHandler.server_version |
class http.server.ThreadingHTTPServer(server_address, RequestHandlerClass)
This class is identical to HTTPServer but uses threads to handle requests by using the ThreadingMixIn. This is useful to handle web browsers pre-opening sockets, on which HTTPServer would wait indefinitely. New in version 3.7. | python.library.http.server#http.server.ThreadingHTTPServer |
id(object)
Return the “identity” of an object. This is an integer which is guaranteed to be unique and constant for this object during its lifetime. Two objects with non-overlapping lifetimes may have the same id() value. CPython implementation detail: This is the address of the object in memory. Raises an auditing event builtins.id with argument id. | python.library.functions#id |
IDLE Source code: Lib/idlelib/ IDLE is Python’s Integrated Development and Learning Environment. IDLE has the following features: coded in 100% pure Python, using the tkinter GUI toolkit cross-platform: works mostly the same on Windows, Unix, and macOS Python shell window (interactive interpreter) with colorizing of code input, output, and error messages multi-window text editor with multiple undo, Python colorizing, smart indent, call tips, auto completion, and other features search within any window, replace within editor windows, and search through multiple files (grep) debugger with persistent breakpoints, stepping, and viewing of global and local namespaces configuration, browsers, and other dialogs Menus IDLE has two main window types, the Shell window and the Editor window. It is possible to have multiple editor windows simultaneously. On Windows and Linux, each has its own top menu. Each menu documented below indicates which window type it is associated with. Output windows, such as used for Edit => Find in Files, are a subtype of editor window. They currently have the same top menu but a different default title and context menu. On macOS, there is one application menu. It dynamically changes according to the window currently selected. It has an IDLE menu, and some entries described below are moved around to conform to Apple guidelines. File menu (Shell and Editor) New File
Create a new file editing window. Open…
Open an existing file with an Open dialog. Recent Files
Open a list of recent files. Click one to open it. Open Module…
Open an existing module (searches sys.path). Class Browser
Show functions, classes, and methods in the current Editor file in a tree structure. In the shell, open a module first. Path Browser
Show sys.path directories, modules, functions, classes and methods in a tree structure. Save
Save the current window to the associated file, if there is one. Windows that have been changed since being opened or last saved have a * before and after the window title. If there is no associated file, do Save As instead. Save As…
Save the current window with a Save As dialog. The file saved becomes the new associated file for the window. Save Copy As…
Save the current window to different file without changing the associated file. Print Window
Print the current window to the default printer. Close
Close the current window (ask to save if unsaved). Exit
Close all windows and quit IDLE (ask to save unsaved windows). Edit menu (Shell and Editor) Undo
Undo the last change to the current window. A maximum of 1000 changes may be undone. Redo
Redo the last undone change to the current window. Cut
Copy selection into the system-wide clipboard; then delete the selection. Copy
Copy selection into the system-wide clipboard. Paste
Insert contents of the system-wide clipboard into the current window. The clipboard functions are also available in context menus. Select All
Select the entire contents of the current window. Find…
Open a search dialog with many options Find Again
Repeat the last search, if there is one. Find Selection
Search for the currently selected string, if there is one. Find in Files…
Open a file search dialog. Put results in a new output window. Replace…
Open a search-and-replace dialog. Go to Line
Move the cursor to the beginning of the line requested and make that line visible. A request past the end of the file goes to the end. Clear any selection and update the line and column status. Show Completions
Open a scrollable list allowing selection of existing names. See Completions in the Editing and navigation section below. Expand Word
Expand a prefix you have typed to match a full word in the same window; repeat to get a different expansion. Show call tip
After an unclosed parenthesis for a function, open a small window with function parameter hints. See Calltips in the Editing and navigation section below. Show surrounding parens
Highlight the surrounding parenthesis. Format menu (Editor window only) Indent Region
Shift selected lines right by the indent width (default 4 spaces). Dedent Region
Shift selected lines left by the indent width (default 4 spaces). Comment Out Region
Insert ## in front of selected lines. Uncomment Region
Remove leading # or ## from selected lines. Tabify Region
Turn leading stretches of spaces into tabs. (Note: We recommend using 4 space blocks to indent Python code.) Untabify Region
Turn all tabs into the correct number of spaces. Toggle Tabs
Open a dialog to switch between indenting with spaces and tabs. New Indent Width
Open a dialog to change indent width. The accepted default by the Python community is 4 spaces. Format Paragraph
Reformat the current blank-line-delimited paragraph in comment block or multiline string or selected line in a string. All lines in the paragraph will be formatted to less than N columns, where N defaults to 72. Strip trailing whitespace
Remove trailing space and other whitespace characters after the last non-whitespace character of a line by applying str.rstrip to each line, including lines within multiline strings. Except for Shell windows, remove extra newlines at the end of the file. Run menu (Editor window only) Run Module
Do Check Module. If no error, restart the shell to clean the environment, then execute the module. Output is displayed in the Shell window. Note that output requires use of print or write. When execution is complete, the Shell retains focus and displays a prompt. At this point, one may interactively explore the result of execution. This is similar to executing a file with python -i file at a command line. Run… Customized
Same as Run Module, but run the module with customized settings. Command Line Arguments extend sys.argv as if passed on a command line. The module can be run in the Shell without restarting. Check Module
Check the syntax of the module currently open in the Editor window. If the module has not been saved IDLE will either prompt the user to save or autosave, as selected in the General tab of the Idle Settings dialog. If there is a syntax error, the approximate location is indicated in the Editor window. Python Shell
Open or wake up the Python Shell window. Shell menu (Shell window only) View Last Restart
Scroll the shell window to the last Shell restart. Restart Shell
Restart the shell to clean the environment and reset display and exception handling. Previous History
Cycle through earlier commands in history which match the current entry. Next History
Cycle through later commands in history which match the current entry. Interrupt Execution
Stop a running program. Debug menu (Shell window only) Go to File/Line
Look on the current line. with the cursor, and the line above for a filename and line number. If found, open the file if not already open, and show the line. Use this to view source lines referenced in an exception traceback and lines found by Find in Files. Also available in the context menu of the Shell window and Output windows. Debugger (toggle)
When activated, code entered in the Shell or run from an Editor will run under the debugger. In the Editor, breakpoints can be set with the context menu. This feature is still incomplete and somewhat experimental. Stack Viewer
Show the stack traceback of the last exception in a tree widget, with access to locals and globals. Auto-open Stack Viewer
Toggle automatically opening the stack viewer on an unhandled exception. Options menu (Shell and Editor) Configure IDLE
Open a configuration dialog and change preferences for the following: fonts, indentation, keybindings, text color themes, startup windows and size, additional help sources, and extensions. On macOS, open the configuration dialog by selecting Preferences in the application menu. For more details, see Setting preferences under Help and preferences. Most configuration options apply to all windows or all future windows. The option items below only apply to the active window. Show/Hide Code Context (Editor Window only)
Open a pane at the top of the edit window which shows the block context of the code which has scrolled above the top of the window. See Code Context in the Editing and Navigation section below. Show/Hide Line Numbers (Editor Window only)
Open a column to the left of the edit window which shows the number of each line of text. The default is off, which may be changed in the preferences (see Setting preferences). Zoom/Restore Height
Toggles the window between normal size and maximum height. The initial size defaults to 40 lines by 80 chars unless changed on the General tab of the Configure IDLE dialog. The maximum height for a screen is determined by momentarily maximizing a window the first time one is zoomed on the screen. Changing screen settings may invalidate the saved height. This toggle has no effect when a window is maximized. Window menu (Shell and Editor) Lists the names of all open windows; select one to bring it to the foreground (deiconifying it if necessary). Help menu (Shell and Editor) About IDLE
Display version, copyright, license, credits, and more. IDLE Help
Display this IDLE document, detailing the menu options, basic editing and navigation, and other tips. Python Docs
Access local Python documentation, if installed, or start a web browser and open docs.python.org showing the latest Python documentation. Turtle Demo
Run the turtledemo module with example Python code and turtle drawings. Additional help sources may be added here with the Configure IDLE dialog under the General tab. See the Help sources subsection below for more on Help menu choices. Context Menus Open a context menu by right-clicking in a window (Control-click on macOS). Context menus have the standard clipboard functions also on the Edit menu. Cut
Copy selection into the system-wide clipboard; then delete the selection. Copy
Copy selection into the system-wide clipboard. Paste
Insert contents of the system-wide clipboard into the current window. Editor windows also have breakpoint functions. Lines with a breakpoint set are specially marked. Breakpoints only have an effect when running under the debugger. Breakpoints for a file are saved in the user’s .idlerc directory. Set Breakpoint
Set a breakpoint on the current line. Clear Breakpoint
Clear the breakpoint on that line. Shell and Output windows also have the following. Go to file/line
Same as in Debug menu. The Shell window also has an output squeezing facility explained in the Python Shell window subsection below. Squeeze
If the cursor is over an output line, squeeze all the output between the code above and the prompt below down to a ‘Squeezed text’ label. Editing and navigation Editor windows IDLE may open editor windows when it starts, depending on settings and how you start IDLE. Thereafter, use the File menu. There can be only one open editor window for a given file. The title bar contains the name of the file, the full path, and the version of Python and IDLE running the window. The status bar contains the line number (‘Ln’) and column number (‘Col’). Line numbers start with 1; column numbers with 0. IDLE assumes that files with a known .py* extension contain Python code and that other files do not. Run Python code with the Run menu. Key bindings In this section, ‘C’ refers to the Control key on Windows and Unix and the Command key on macOS.
Backspace deletes to the left; Del deletes to the right
C-Backspace delete word left; C-Del delete word to the right Arrow keys and Page Up/Page Down to move around
C-LeftArrow and C-RightArrow moves by words
Home/End go to begin/end of line
C-Home/C-End go to begin/end of file
Some useful Emacs bindings are inherited from Tcl/Tk:
C-a beginning of line
C-e end of line
C-k kill line (but doesn’t put it in clipboard)
C-l center window around the insertion point
C-b go backward one character without deleting (usually you can also use the cursor key for this)
C-f go forward one character without deleting (usually you can also use the cursor key for this)
C-p go up one line (usually you can also use the cursor key for this)
C-d delete next character Standard keybindings (like C-c to copy and C-v to paste) may work. Keybindings are selected in the Configure IDLE dialog. Automatic indentation After a block-opening statement, the next line is indented by 4 spaces (in the Python Shell window by one tab). After certain keywords (break, return etc.) the next line is dedented. In leading indentation, Backspace deletes up to 4 spaces if they are there. Tab inserts spaces (in the Python Shell window one tab), number depends on Indent width. Currently, tabs are restricted to four spaces due to Tcl/Tk limitations. See also the indent/dedent region commands on the Format menu. Completions Completions are supplied, when requested and available, for module names, attributes of classes or functions, or filenames. Each request method displays a completion box with existing names. (See tab completions below for an exception.) For any box, change the name being completed and the item highlighted in the box by typing and deleting characters; by hitting Up, Down, PageUp, PageDown, Home, and End keys; and by a single click within the box. Close the box with Escape, Enter, and double Tab keys or clicks outside the box. A double click within the box selects and closes. One way to open a box is to type a key character and wait for a predefined interval. This defaults to 2 seconds; customize it in the settings dialog. (To prevent auto popups, set the delay to a large number of milliseconds, such as 100000000.) For imported module names or class or function attributes, type ‘.’. For filenames in the root directory, type os.sep or os.altsep immediately after an opening quote. (On Windows, one can specify a drive first.) Move into subdirectories by typing a directory name and a separator. Instead of waiting, or after a box is closed, open a completion box immediately with Show Completions on the Edit menu. The default hot key is C-space. If one types a prefix for the desired name before opening the box, the first match or near miss is made visible. The result is the same as if one enters a prefix after the box is displayed. Show Completions after a quote completes filenames in the current directory instead of a root directory. Hitting Tab after a prefix usually has the same effect as Show Completions. (With no prefix, it indents.) However, if there is only one match to the prefix, that match is immediately added to the editor text without opening a box. Invoking ‘Show Completions’, or hitting Tab after a prefix, outside of a string and without a preceding ‘.’ opens a box with keywords, builtin names, and available module-level names. When editing code in an editor (as oppose to Shell), increase the available module-level names by running your code and not restarting the Shell thereafter. This is especially useful after adding imports at the top of a file. This also increases possible attribute completions. Completion boxes intially exclude names beginning with ‘_’ or, for modules, not included in ‘__all__’. The hidden names can be accessed by typing ‘_’ after ‘.’, either before or after the box is opened. Calltips A calltip is shown automatically when one types ( after the name of an accessible function. A function name expression may include dots and subscripts. A calltip remains until it is clicked, the cursor is moved out of the argument area, or ) is typed. Whenever the cursor is in the argument part of a definition, select Edit and “Show Call Tip” on the menu or enter its shortcut to display a calltip. The calltip consists of the function’s signature and docstring up to the latter’s first blank line or the fifth non-blank line. (Some builtin functions lack an accessible signature.) A ‘/’ or ‘*’ in the signature indicates that the preceding or following arguments are passed by position or name (keyword) only. Details are subject to change. In Shell, the accessible functions depends on what modules have been imported into the user process, including those imported by Idle itself, and which definitions have been run, all since the last restart. For example, restart the Shell and enter itertools.count(. A calltip appears because Idle imports itertools into the user process for its own use. (This could change.) Enter turtle.write( and nothing appears. Idle does not itself import turtle. The menu entry and shortcut also do nothing. Enter import turtle. Thereafter, turtle.write( will display a calltip. In an editor, import statements have no effect until one runs the file. One might want to run a file after writing import statements, after adding function definitions, or after opening an existing file. Code Context Within an editor window containing Python code, code context can be toggled in order to show or hide a pane at the top of the window. When shown, this pane freezes the opening lines for block code, such as those beginning with class, def, or if keywords, that would have otherwise scrolled out of view. The size of the pane will be expanded and contracted as needed to show the all current levels of context, up to the maximum number of lines defined in the Configure IDLE dialog (which defaults to 15). If there are no current context lines and the feature is toggled on, a single blank line will display. Clicking on a line in the context pane will move that line to the top of the editor. The text and background colors for the context pane can be configured under the Highlights tab in the Configure IDLE dialog. Python Shell window With IDLE’s Shell, one enters, edits, and recalls complete statements. Most consoles and terminals only work with a single physical line at a time. When one pastes code into Shell, it is not compiled and possibly executed until one hits Return. One may edit pasted code first. If one pastes more that one statement into Shell, the result will be a SyntaxError when multiple statements are compiled as if they were one. The editing features described in previous subsections work when entering code interactively. IDLE’s Shell window also responds to the following keys.
C-c interrupts executing command
C-d sends end-of-file; closes window if typed at a >>> prompt
Alt-/ (Expand word) is also useful to reduce typing Command history
Alt-p retrieves previous command matching what you have typed. On macOS use C-p.
Alt-n retrieves next. On macOS use C-n.
Return while on any previous command retrieves that command Text colors Idle defaults to black on white text, but colors text with special meanings. For the shell, these are shell output, shell error, user output, and user error. For Python code, at the shell prompt or in an editor, these are keywords, builtin class and function names, names following class and def, strings, and comments. For any text window, these are the cursor (when present), found text (when possible), and selected text. Text coloring is done in the background, so uncolorized text is occasionally visible. To change the color scheme, use the Configure IDLE dialog Highlighting tab. The marking of debugger breakpoint lines in the editor and text in popups and dialogs is not user-configurable. Startup and code execution Upon startup with the -s option, IDLE will execute the file referenced by the environment variables IDLESTARTUP or PYTHONSTARTUP. IDLE first checks for IDLESTARTUP; if IDLESTARTUP is present the file referenced is run. If IDLESTARTUP is not present, IDLE checks for PYTHONSTARTUP. Files referenced by these environment variables are convenient places to store functions that are used frequently from the IDLE shell, or for executing import statements to import common modules. In addition, Tk also loads a startup file if it is present. Note that the Tk file is loaded unconditionally. This additional file is .Idle.py and is looked for in the user’s home directory. Statements in this file will be executed in the Tk namespace, so this file is not useful for importing functions to be used from IDLE’s Python shell. Command line usage idle.py [-c command] [-d] [-e] [-h] [-i] [-r file] [-s] [-t title] [-] [arg] ...
-c command run command in the shell window
-d enable debugger and open shell window
-e open editor window
-h print help message with legal combinations and exit
-i open shell window
-r file run file in shell window
-s run $IDLESTARTUP or $PYTHONSTARTUP first, in shell window
-t title set title of shell window
- run stdin in shell (- must be last option before args)
If there are arguments: If -, -c, or r is used, all arguments are placed in sys.argv[1:...] and sys.argv[0] is set to '', '-c', or '-r'. No editor window is opened, even if that is the default set in the Options dialog. Otherwise, arguments are files opened for editing and sys.argv reflects the arguments passed to IDLE itself. Startup failure IDLE uses a socket to communicate between the IDLE GUI process and the user code execution process. A connection must be established whenever the Shell starts or restarts. (The latter is indicated by a divider line that says ‘RESTART’). If the user process fails to connect to the GUI process, it usually displays a Tk error box with a ‘cannot connect’ message that directs the user here. It then exits. One specific connection failure on Unix systems results from misconfigured masquerading rules somewhere in a system’s network setup. When IDLE is started from a terminal, one will see a message starting with ** Invalid host:. The valid value is 127.0.0.1 (idlelib.rpc.LOCALHOST). One can diagnose with tcpconnect -irv 127.0.0.1 6543 in one terminal window and tcplisten <same args> in another. A common cause of failure is a user-written file with the same name as a standard library module, such as random.py and tkinter.py. When such a file is located in the same directory as a file that is about to be run, IDLE cannot import the stdlib file. The current fix is to rename the user file. Though less common than in the past, an antivirus or firewall program may stop the connection. If the program cannot be taught to allow the connection, then it must be turned off for IDLE to work. It is safe to allow this internal connection because no data is visible on external ports. A similar problem is a network mis-configuration that blocks connections. Python installation issues occasionally stop IDLE: multiple versions can clash, or a single installation might need admin access. If one undo the clash, or cannot or does not want to run as admin, it might be easiest to completely remove Python and start over. A zombie pythonw.exe process could be a problem. On Windows, use Task Manager to check for one and stop it if there is. Sometimes a restart initiated by a program crash or Keyboard Interrupt (control-C) may fail to connect. Dismissing the error box or using Restart Shell on the Shell menu may fix a temporary problem. When IDLE first starts, it attempts to read user configuration files in ~/.idlerc/ (~ is one’s home directory). If there is a problem, an error message should be displayed. Leaving aside random disk glitches, this can be prevented by never editing the files by hand. Instead, use the configuration dialog, under Options. Once there is an error in a user configuration file, the best solution may be to delete it and start over with the settings dialog. If IDLE quits with no message, and it was not started from a console, try starting it from a console or terminal (python -m idlelib) and see if this results in an error message. On Unix-based systems with tcl/tk older than 8.6.11 (see About IDLE) certain characters of certain fonts can cause a tk failure with a message to the terminal. This can happen either if one starts IDLE to edit a file with such a character or later when entering such a character. If one cannot upgrade tcl/tk, then re-configure IDLE to use a font that works better. Running user code With rare exceptions, the result of executing Python code with IDLE is intended to be the same as executing the same code by the default method, directly with Python in a text-mode system console or terminal window. However, the different interface and operation occasionally affect visible results. For instance, sys.modules starts with more entries, and threading.active_count() returns 2 instead of 1. By default, IDLE runs user code in a separate OS process rather than in the user interface process that runs the shell and editor. In the execution process, it replaces sys.stdin, sys.stdout, and sys.stderr with objects that get input from and send output to the Shell window. The original values stored in sys.__stdin__, sys.__stdout__, and sys.__stderr__ are not touched, but may be None. Sending print output from one process to a text widget in another is slower than printing to a system terminal in the same process. This has the most effect when printing multiple arguments, as the string for each argument, each separator, the newline are sent separately. For development, this is usually not a problem, but if one wants to print faster in IDLE, format and join together everything one wants displayed together and then print a single string. Both format strings and str.join() can help combine fields and lines. IDLE’s standard stream replacements are not inherited by subprocesses created in the execution process, whether directly by user code or by modules such as multiprocessing. If such subprocess use input from sys.stdin or print or write to sys.stdout or sys.stderr, IDLE should be started in a command line window. The secondary subprocess will then be attached to that window for input and output. If sys is reset by user code, such as with importlib.reload(sys), IDLE’s changes are lost and input from the keyboard and output to the screen will not work correctly. When Shell has the focus, it controls the keyboard and screen. This is normally transparent, but functions that directly access the keyboard and screen will not work. These include system-specific functions that determine whether a key has been pressed and if so, which. The IDLE code running in the execution process adds frames to the call stack that would not be there otherwise. IDLE wraps sys.getrecursionlimit and sys.setrecursionlimit to reduce the effect of the additional stack frames. When user code raises SystemExit either directly or by calling sys.exit, IDLE returns to a Shell prompt instead of exiting. User output in Shell When a program outputs text, the result is determined by the corresponding output device. When IDLE executes user code, sys.stdout and sys.stderr are connected to the display area of IDLE’s Shell. Some of its features are inherited from the underlying Tk Text widget. Others are programmed additions. Where it matters, Shell is designed for development rather than production runs. For instance, Shell never throws away output. A program that sends unlimited output to Shell will eventually fill memory, resulting in a memory error. In contrast, some system text windows only keep the last n lines of output. A Windows console, for instance, keeps a user-settable 1 to 9999 lines, with 300 the default. A Tk Text widget, and hence IDLE’s Shell, displays characters (codepoints) in the BMP (Basic Multilingual Plane) subset of Unicode. Which characters are displayed with a proper glyph and which with a replacement box depends on the operating system and installed fonts. Tab characters cause the following text to begin after the next tab stop. (They occur every 8 ‘characters’). Newline characters cause following text to appear on a new line. Other control characters are ignored or displayed as a space, box, or something else, depending on the operating system and font. (Moving the text cursor through such output with arrow keys may exhibit some surprising spacing behavior.) >>> s = 'a\tb\a<\x02><\r>\bc\nd' # Enter 22 chars.
>>> len(s)
14
>>> s # Display repr(s)
'a\tb\x07<\x02><\r>\x08c\nd'
>>> print(s, end='') # Display s as is.
# Result varies by OS and font. Try it.
The repr function is used for interactive echo of expression values. It returns an altered version of the input string in which control codes, some BMP codepoints, and all non-BMP codepoints are replaced with escape codes. As demonstrated above, it allows one to identify the characters in a string, regardless of how they are displayed. Normal and error output are generally kept separate (on separate lines) from code input and each other. They each get different highlight colors. For SyntaxError tracebacks, the normal ‘^’ marking where the error was detected is replaced by coloring the text with an error highlight. When code run from a file causes other exceptions, one may right click on a traceback line to jump to the corresponding line in an IDLE editor. The file will be opened if necessary. Shell has a special facility for squeezing output lines down to a ‘Squeezed text’ label. This is done automatically for output over N lines (N = 50 by default). N can be changed in the PyShell section of the General page of the Settings dialog. Output with fewer lines can be squeezed by right clicking on the output. This can be useful lines long enough to slow down scrolling. Squeezed output is expanded in place by double-clicking the label. It can also be sent to the clipboard or a separate view window by right-clicking the label. Developing tkinter applications IDLE is intentionally different from standard Python in order to facilitate development of tkinter programs. Enter import tkinter as tk;
root = tk.Tk() in standard Python and nothing appears. Enter the same in IDLE and a tk window appears. In standard Python, one must also enter root.update() to see the window. IDLE does the equivalent in the background, about 20 times a second, which is about every 50 milliseconds. Next enter b = tk.Button(root, text='button'); b.pack(). Again, nothing visibly changes in standard Python until one enters root.update(). Most tkinter programs run root.mainloop(), which usually does not return until the tk app is destroyed. If the program is run with python -i or from an IDLE editor, a >>> shell prompt does not appear until mainloop() returns, at which time there is nothing left to interact with. When running a tkinter program from an IDLE editor, one can comment out the mainloop call. One then gets a shell prompt immediately and can interact with the live application. One just has to remember to re-enable the mainloop call when running in standard Python. Running without a subprocess By default, IDLE executes user code in a separate subprocess via a socket, which uses the internal loopback interface. This connection is not externally visible and no data is sent to or received from the Internet. If firewall software complains anyway, you can ignore it. If the attempt to make the socket connection fails, Idle will notify you. Such failures are sometimes transient, but if persistent, the problem may be either a firewall blocking the connection or misconfiguration of a particular system. Until the problem is fixed, one can run Idle with the -n command line switch. If IDLE is started with the -n command line switch it will run in a single process and will not create the subprocess which runs the RPC Python execution server. This can be useful if Python cannot create the subprocess or the RPC socket interface on your platform. However, in this mode user code is not isolated from IDLE itself. Also, the environment is not restarted when Run/Run Module (F5) is selected. If your code has been modified, you must reload() the affected modules and re-import any specific items (e.g. from foo import baz) if the changes are to take effect. For these reasons, it is preferable to run IDLE with the default subprocess if at all possible. Deprecated since version 3.4. Help and preferences Help sources Help menu entry “IDLE Help” displays a formatted html version of the IDLE chapter of the Library Reference. The result, in a read-only tkinter text window, is close to what one sees in a web browser. Navigate through the text with a mousewheel, the scrollbar, or up and down arrow keys held down. Or click the TOC (Table of Contents) button and select a section header in the opened box. Help menu entry “Python Docs” opens the extensive sources of help, including tutorials, available at docs.python.org/x.y, where ‘x.y’ is the currently running Python version. If your system has an off-line copy of the docs (this may be an installation option), that will be opened instead. Selected URLs can be added or removed from the help menu at any time using the General tab of the Configure IDLE dialog. Setting preferences The font preferences, highlighting, keys, and general preferences can be changed via Configure IDLE on the Option menu. Non-default user settings are saved in a .idlerc directory in the user’s home directory. Problems caused by bad user configuration files are solved by editing or deleting one or more of the files in .idlerc. On the Font tab, see the text sample for the effect of font face and size on multiple characters in multiple languages. Edit the sample to add other characters of personal interest. Use the sample to select monospaced fonts. If particular characters have problems in Shell or an editor, add them to the top of the sample and try changing first size and then font. On the Highlights and Keys tab, select a built-in or custom color theme and key set. To use a newer built-in color theme or key set with older IDLEs, save it as a new custom theme or key set and it well be accessible to older IDLEs. IDLE on macOS Under System Preferences: Dock, one can set “Prefer tabs when opening documents” to “Always”. This setting is not compatible with the tk/tkinter GUI framework used by IDLE, and it breaks a few IDLE features. Extensions IDLE contains an extension facility. Preferences for extensions can be changed with the Extensions tab of the preferences dialog. See the beginning of config-extensions.def in the idlelib directory for further information. The only current default extension is zzdummy, an example also used for testing. | python.library.idle |
imaplib — IMAP4 protocol client Source code: Lib/imaplib.py This module defines three classes, IMAP4, IMAP4_SSL and IMAP4_stream, which encapsulate a connection to an IMAP4 server and implement a large subset of the IMAP4rev1 client protocol as defined in RFC 2060. It is backward compatible with IMAP4 (RFC 1730) servers, but note that the STATUS command is not supported in IMAP4. Three classes are provided by the imaplib module, IMAP4 is the base class:
class imaplib.IMAP4(host='', port=IMAP4_PORT, timeout=None)
This class implements the actual IMAP4 protocol. The connection is created and protocol version (IMAP4 or IMAP4rev1) is determined when the instance is initialized. If host is not specified, '' (the local host) is used. If port is omitted, the standard IMAP4 port (143) is used. The optional timeout parameter specifies a timeout in seconds for the connection attempt. If timeout is not given or is None, the global default socket timeout is used. The IMAP4 class supports the with statement. When used like this, the IMAP4 LOGOUT command is issued automatically when the with statement exits. E.g.: >>> from imaplib import IMAP4
>>> with IMAP4("domain.org") as M:
... M.noop()
...
('OK', [b'Nothing Accomplished. d25if65hy903weo.87'])
Changed in version 3.5: Support for the with statement was added. Changed in version 3.9: The optional timeout parameter was added.
Three exceptions are defined as attributes of the IMAP4 class:
exception IMAP4.error
Exception raised on any errors. The reason for the exception is passed to the constructor as a string.
exception IMAP4.abort
IMAP4 server errors cause this exception to be raised. This is a sub-class of IMAP4.error. Note that closing the instance and instantiating a new one will usually allow recovery from this exception.
exception IMAP4.readonly
This exception is raised when a writable mailbox has its status changed by the server. This is a sub-class of IMAP4.error. Some other client now has write permission, and the mailbox will need to be re-opened to re-obtain write permission.
There’s also a subclass for secure connections:
class imaplib.IMAP4_SSL(host='', port=IMAP4_SSL_PORT, keyfile=None, certfile=None, ssl_context=None, timeout=None)
This is a subclass derived from IMAP4 that connects over an SSL encrypted socket (to use this class you need a socket module that was compiled with SSL support). If host is not specified, '' (the local host) is used. If port is omitted, the standard IMAP4-over-SSL port (993) is used. ssl_context is a ssl.SSLContext object which allows bundling SSL configuration options, certificates and private keys into a single (potentially long-lived) structure. Please read Security considerations for best practices. keyfile and certfile are a legacy alternative to ssl_context - they can point to PEM-formatted private key and certificate chain files for the SSL connection. Note that the keyfile/certfile parameters are mutually exclusive with ssl_context, a ValueError is raised if keyfile/certfile is provided along with ssl_context. The optional timeout parameter specifies a timeout in seconds for the connection attempt. If timeout is not given or is None, the global default socket timeout is used. Changed in version 3.3: ssl_context parameter was added. Changed in version 3.4: The class now supports hostname check with ssl.SSLContext.check_hostname and Server Name Indication (see ssl.HAS_SNI). Deprecated since version 3.6: keyfile and certfile are deprecated in favor of ssl_context. Please use ssl.SSLContext.load_cert_chain() instead, or let ssl.create_default_context() select the system’s trusted CA certificates for you. Changed in version 3.9: The optional timeout parameter was added.
The second subclass allows for connections created by a child process:
class imaplib.IMAP4_stream(command)
This is a subclass derived from IMAP4 that connects to the stdin/stdout file descriptors created by passing command to subprocess.Popen().
The following utility functions are defined:
imaplib.Internaldate2tuple(datestr)
Parse an IMAP4 INTERNALDATE string and return corresponding local time. The return value is a time.struct_time tuple or None if the string has wrong format.
imaplib.Int2AP(num)
Converts an integer into a bytes representation using characters from the set [A .. P].
imaplib.ParseFlags(flagstr)
Converts an IMAP4 FLAGS response to a tuple of individual flags.
imaplib.Time2Internaldate(date_time)
Convert date_time to an IMAP4 INTERNALDATE representation. The return value is a string in the form: "DD-Mmm-YYYY HH:MM:SS
+HHMM" (including double-quotes). The date_time argument can be a number (int or float) representing seconds since epoch (as returned by time.time()), a 9-tuple representing local time an instance of time.struct_time (as returned by time.localtime()), an aware instance of datetime.datetime, or a double-quoted string. In the last case, it is assumed to already be in the correct format.
Note that IMAP4 message numbers change as the mailbox changes; in particular, after an EXPUNGE command performs deletions the remaining messages are renumbered. So it is highly advisable to use UIDs instead, with the UID command. At the end of the module, there is a test section that contains a more extensive example of usage. See also Documents describing the protocol, sources for servers implementing it, by the University of Washington’s IMAP Information Center can all be found at (Source Code) https://github.com/uw-imap/imap (Not Maintained). IMAP4 Objects All IMAP4rev1 commands are represented by methods of the same name, either upper-case or lower-case. All arguments to commands are converted to strings, except for AUTHENTICATE, and the last argument to APPEND which is passed as an IMAP4 literal. If necessary (the string contains IMAP4 protocol-sensitive characters and isn’t enclosed with either parentheses or double quotes) each string is quoted. However, the password argument to the LOGIN command is always quoted. If you want to avoid having an argument string quoted (eg: the flags argument to STORE) then enclose the string in parentheses (eg: r'(\Deleted)'). Each command returns a tuple: (type, [data, ...]) where type is usually 'OK' or 'NO', and data is either the text from the command response, or mandated results from the command. Each data is either a bytes, or a tuple. If a tuple, then the first part is the header of the response, and the second part contains the data (ie: ‘literal’ value). The message_set options to commands below is a string specifying one or more messages to be acted upon. It may be a simple message number ('1'), a range of message numbers ('2:4'), or a group of non-contiguous ranges separated by commas ('1:3,6:9'). A range can contain an asterisk to indicate an infinite upper bound ('3:*'). An IMAP4 instance has the following methods:
IMAP4.append(mailbox, flags, date_time, message)
Append message to named mailbox.
IMAP4.authenticate(mechanism, authobject)
Authenticate command — requires response processing. mechanism specifies which authentication mechanism is to be used - it should appear in the instance variable capabilities in the form AUTH=mechanism. authobject must be a callable object: data = authobject(response)
It will be called to process server continuation responses; the response argument it is passed will be bytes. It should return bytes data that will be base64 encoded and sent to the server. It should return None if the client abort response * should be sent instead. Changed in version 3.5: string usernames and passwords are now encoded to utf-8 instead of being limited to ASCII.
IMAP4.check()
Checkpoint mailbox on server.
IMAP4.close()
Close currently selected mailbox. Deleted messages are removed from writable mailbox. This is the recommended command before LOGOUT.
IMAP4.copy(message_set, new_mailbox)
Copy message_set messages onto end of new_mailbox.
IMAP4.create(mailbox)
Create new mailbox named mailbox.
IMAP4.delete(mailbox)
Delete old mailbox named mailbox.
IMAP4.deleteacl(mailbox, who)
Delete the ACLs (remove any rights) set for who on mailbox.
IMAP4.enable(capability)
Enable capability (see RFC 5161). Most capabilities do not need to be enabled. Currently only the UTF8=ACCEPT capability is supported (see RFC 6855). New in version 3.5: The enable() method itself, and RFC 6855 support.
IMAP4.expunge()
Permanently remove deleted items from selected mailbox. Generates an EXPUNGE response for each deleted message. Returned data contains a list of EXPUNGE message numbers in order received.
IMAP4.fetch(message_set, message_parts)
Fetch (parts of) messages. message_parts should be a string of message part names enclosed within parentheses, eg: "(UID BODY[TEXT])". Returned data are tuples of message part envelope and data.
IMAP4.getacl(mailbox)
Get the ACLs for mailbox. The method is non-standard, but is supported by the Cyrus server.
IMAP4.getannotation(mailbox, entry, attribute)
Retrieve the specified ANNOTATIONs for mailbox. The method is non-standard, but is supported by the Cyrus server.
IMAP4.getquota(root)
Get the quota root’s resource usage and limits. This method is part of the IMAP4 QUOTA extension defined in rfc2087.
IMAP4.getquotaroot(mailbox)
Get the list of quota roots for the named mailbox. This method is part of the IMAP4 QUOTA extension defined in rfc2087.
IMAP4.list([directory[, pattern]])
List mailbox names in directory matching pattern. directory defaults to the top-level mail folder, and pattern defaults to match anything. Returned data contains a list of LIST responses.
IMAP4.login(user, password)
Identify the client using a plaintext password. The password will be quoted.
IMAP4.login_cram_md5(user, password)
Force use of CRAM-MD5 authentication when identifying the client to protect the password. Will only work if the server CAPABILITY response includes the phrase AUTH=CRAM-MD5.
IMAP4.logout()
Shutdown connection to server. Returns server BYE response. Changed in version 3.8: The method no longer ignores silently arbitrary exceptions.
IMAP4.lsub(directory='""', pattern='*')
List subscribed mailbox names in directory matching pattern. directory defaults to the top level directory and pattern defaults to match any mailbox. Returned data are tuples of message part envelope and data.
IMAP4.myrights(mailbox)
Show my ACLs for a mailbox (i.e. the rights that I have on mailbox).
IMAP4.namespace()
Returns IMAP namespaces as defined in RFC 2342.
IMAP4.noop()
Send NOOP to server.
IMAP4.open(host, port, timeout=None)
Opens socket to port at host. The optional timeout parameter specifies a timeout in seconds for the connection attempt. If timeout is not given or is None, the global default socket timeout is used. Also note that if the timeout parameter is set to be zero, it will raise a ValueError to reject creating a non-blocking socket. This method is implicitly called by the IMAP4 constructor. The connection objects established by this method will be used in the IMAP4.read(), IMAP4.readline(), IMAP4.send(), and IMAP4.shutdown() methods. You may override this method. Raises an auditing event imaplib.open with arguments self, host, port. Changed in version 3.9: The timeout parameter was added.
IMAP4.partial(message_num, message_part, start, length)
Fetch truncated part of a message. Returned data is a tuple of message part envelope and data.
IMAP4.proxyauth(user)
Assume authentication as user. Allows an authorised administrator to proxy into any user’s mailbox.
IMAP4.read(size)
Reads size bytes from the remote server. You may override this method.
IMAP4.readline()
Reads one line from the remote server. You may override this method.
IMAP4.recent()
Prompt server for an update. Returned data is None if no new messages, else value of RECENT response.
IMAP4.rename(oldmailbox, newmailbox)
Rename mailbox named oldmailbox to newmailbox.
IMAP4.response(code)
Return data for response code if received, or None. Returns the given code, instead of the usual type.
IMAP4.search(charset, criterion[, ...])
Search mailbox for matching messages. charset may be None, in which case no CHARSET will be specified in the request to the server. The IMAP protocol requires that at least one criterion be specified; an exception will be raised when the server returns an error. charset must be None if the UTF8=ACCEPT capability was enabled using the enable() command. Example: # M is a connected IMAP4 instance...
typ, msgnums = M.search(None, 'FROM', '"LDJ"')
# or:
typ, msgnums = M.search(None, '(FROM "LDJ")')
IMAP4.select(mailbox='INBOX', readonly=False)
Select a mailbox. Returned data is the count of messages in mailbox (EXISTS response). The default mailbox is 'INBOX'. If the readonly flag is set, modifications to the mailbox are not allowed.
IMAP4.send(data)
Sends data to the remote server. You may override this method. Raises an auditing event imaplib.send with arguments self, data.
IMAP4.setacl(mailbox, who, what)
Set an ACL for mailbox. The method is non-standard, but is supported by the Cyrus server.
IMAP4.setannotation(mailbox, entry, attribute[, ...])
Set ANNOTATIONs for mailbox. The method is non-standard, but is supported by the Cyrus server.
IMAP4.setquota(root, limits)
Set the quota root’s resource limits. This method is part of the IMAP4 QUOTA extension defined in rfc2087.
IMAP4.shutdown()
Close connection established in open. This method is implicitly called by IMAP4.logout(). You may override this method.
IMAP4.socket()
Returns socket instance used to connect to server.
IMAP4.sort(sort_criteria, charset, search_criterion[, ...])
The sort command is a variant of search with sorting semantics for the results. Returned data contains a space separated list of matching message numbers. Sort has two arguments before the search_criterion argument(s); a parenthesized list of sort_criteria, and the searching charset. Note that unlike search, the searching charset argument is mandatory. There is also a uid sort command which corresponds to sort the way that uid search corresponds to search. The sort command first searches the mailbox for messages that match the given searching criteria using the charset argument for the interpretation of strings in the searching criteria. It then returns the numbers of matching messages. This is an IMAP4rev1 extension command.
IMAP4.starttls(ssl_context=None)
Send a STARTTLS command. The ssl_context argument is optional and should be a ssl.SSLContext object. This will enable encryption on the IMAP connection. Please read Security considerations for best practices. New in version 3.2. Changed in version 3.4: The method now supports hostname check with ssl.SSLContext.check_hostname and Server Name Indication (see ssl.HAS_SNI).
IMAP4.status(mailbox, names)
Request named status conditions for mailbox.
IMAP4.store(message_set, command, flag_list)
Alters flag dispositions for messages in mailbox. command is specified by section 6.4.6 of RFC 2060 as being one of “FLAGS”, “+FLAGS”, or “-FLAGS”, optionally with a suffix of “.SILENT”. For example, to set the delete flag on all messages: typ, data = M.search(None, 'ALL')
for num in data[0].split():
M.store(num, '+FLAGS', '\\Deleted')
M.expunge()
Note Creating flags containing ‘]’ (for example: “[test]”) violates RFC 3501 (the IMAP protocol). However, imaplib has historically allowed creation of such tags, and popular IMAP servers, such as Gmail, accept and produce such flags. There are non-Python programs which also create such tags. Although it is an RFC violation and IMAP clients and servers are supposed to be strict, imaplib nonetheless continues to allow such tags to be created for backward compatibility reasons, and as of Python 3.6, handles them if they are sent from the server, since this improves real-world compatibility.
IMAP4.subscribe(mailbox)
Subscribe to new mailbox.
IMAP4.thread(threading_algorithm, charset, search_criterion[, ...])
The thread command is a variant of search with threading semantics for the results. Returned data contains a space separated list of thread members. Thread members consist of zero or more messages numbers, delimited by spaces, indicating successive parent and child. Thread has two arguments before the search_criterion argument(s); a threading_algorithm, and the searching charset. Note that unlike search, the searching charset argument is mandatory. There is also a uid thread command which corresponds to thread the way that uid
search corresponds to search. The thread command first searches the mailbox for messages that match the given searching criteria using the charset argument for the interpretation of strings in the searching criteria. It then returns the matching messages threaded according to the specified threading algorithm. This is an IMAP4rev1 extension command.
IMAP4.uid(command, arg[, ...])
Execute command args with messages identified by UID, rather than message number. Returns response appropriate to command. At least one argument must be supplied; if none are provided, the server will return an error and an exception will be raised.
IMAP4.unsubscribe(mailbox)
Unsubscribe from old mailbox.
IMAP4.unselect()
imaplib.IMAP4.unselect() frees server’s resources associated with the selected mailbox and returns the server to the authenticated state. This command performs the same actions as imaplib.IMAP4.close(), except that no messages are permanently removed from the currently selected mailbox. New in version 3.9.
IMAP4.xatom(name[, ...])
Allow simple extension commands notified by server in CAPABILITY response.
The following attributes are defined on instances of IMAP4:
IMAP4.PROTOCOL_VERSION
The most recent supported protocol in the CAPABILITY response from the server.
IMAP4.debug
Integer value to control debugging output. The initialize value is taken from the module variable Debug. Values greater than three trace each command.
IMAP4.utf8_enabled
Boolean value that is normally False, but is set to True if an enable() command is successfully issued for the UTF8=ACCEPT capability. New in version 3.5.
IMAP4 Example Here is a minimal example (without error checking) that opens a mailbox and retrieves and prints all messages: import getpass, imaplib
M = imaplib.IMAP4()
M.login(getpass.getuser(), getpass.getpass())
M.select()
typ, data = M.search(None, 'ALL')
for num in data[0].split():
typ, data = M.fetch(num, '(RFC822)')
print('Message %s\n%s\n' % (num, data[0][1]))
M.close()
M.logout() | python.library.imaplib |
class imaplib.IMAP4(host='', port=IMAP4_PORT, timeout=None)
This class implements the actual IMAP4 protocol. The connection is created and protocol version (IMAP4 or IMAP4rev1) is determined when the instance is initialized. If host is not specified, '' (the local host) is used. If port is omitted, the standard IMAP4 port (143) is used. The optional timeout parameter specifies a timeout in seconds for the connection attempt. If timeout is not given or is None, the global default socket timeout is used. The IMAP4 class supports the with statement. When used like this, the IMAP4 LOGOUT command is issued automatically when the with statement exits. E.g.: >>> from imaplib import IMAP4
>>> with IMAP4("domain.org") as M:
... M.noop()
...
('OK', [b'Nothing Accomplished. d25if65hy903weo.87'])
Changed in version 3.5: Support for the with statement was added. Changed in version 3.9: The optional timeout parameter was added. | python.library.imaplib#imaplib.IMAP4 |
exception IMAP4.abort
IMAP4 server errors cause this exception to be raised. This is a sub-class of IMAP4.error. Note that closing the instance and instantiating a new one will usually allow recovery from this exception. | python.library.imaplib#imaplib.IMAP4.abort |
IMAP4.append(mailbox, flags, date_time, message)
Append message to named mailbox. | python.library.imaplib#imaplib.IMAP4.append |
IMAP4.authenticate(mechanism, authobject)
Authenticate command — requires response processing. mechanism specifies which authentication mechanism is to be used - it should appear in the instance variable capabilities in the form AUTH=mechanism. authobject must be a callable object: data = authobject(response)
It will be called to process server continuation responses; the response argument it is passed will be bytes. It should return bytes data that will be base64 encoded and sent to the server. It should return None if the client abort response * should be sent instead. Changed in version 3.5: string usernames and passwords are now encoded to utf-8 instead of being limited to ASCII. | python.library.imaplib#imaplib.IMAP4.authenticate |
IMAP4.check()
Checkpoint mailbox on server. | python.library.imaplib#imaplib.IMAP4.check |
IMAP4.close()
Close currently selected mailbox. Deleted messages are removed from writable mailbox. This is the recommended command before LOGOUT. | python.library.imaplib#imaplib.IMAP4.close |
IMAP4.copy(message_set, new_mailbox)
Copy message_set messages onto end of new_mailbox. | python.library.imaplib#imaplib.IMAP4.copy |
IMAP4.create(mailbox)
Create new mailbox named mailbox. | python.library.imaplib#imaplib.IMAP4.create |
IMAP4.debug
Integer value to control debugging output. The initialize value is taken from the module variable Debug. Values greater than three trace each command. | python.library.imaplib#imaplib.IMAP4.debug |
IMAP4.delete(mailbox)
Delete old mailbox named mailbox. | python.library.imaplib#imaplib.IMAP4.delete |
IMAP4.deleteacl(mailbox, who)
Delete the ACLs (remove any rights) set for who on mailbox. | python.library.imaplib#imaplib.IMAP4.deleteacl |
IMAP4.enable(capability)
Enable capability (see RFC 5161). Most capabilities do not need to be enabled. Currently only the UTF8=ACCEPT capability is supported (see RFC 6855). New in version 3.5: The enable() method itself, and RFC 6855 support. | python.library.imaplib#imaplib.IMAP4.enable |
exception IMAP4.error
Exception raised on any errors. The reason for the exception is passed to the constructor as a string. | python.library.imaplib#imaplib.IMAP4.error |
IMAP4.expunge()
Permanently remove deleted items from selected mailbox. Generates an EXPUNGE response for each deleted message. Returned data contains a list of EXPUNGE message numbers in order received. | python.library.imaplib#imaplib.IMAP4.expunge |
IMAP4.fetch(message_set, message_parts)
Fetch (parts of) messages. message_parts should be a string of message part names enclosed within parentheses, eg: "(UID BODY[TEXT])". Returned data are tuples of message part envelope and data. | python.library.imaplib#imaplib.IMAP4.fetch |
IMAP4.getacl(mailbox)
Get the ACLs for mailbox. The method is non-standard, but is supported by the Cyrus server. | python.library.imaplib#imaplib.IMAP4.getacl |
IMAP4.getannotation(mailbox, entry, attribute)
Retrieve the specified ANNOTATIONs for mailbox. The method is non-standard, but is supported by the Cyrus server. | python.library.imaplib#imaplib.IMAP4.getannotation |
IMAP4.getquota(root)
Get the quota root’s resource usage and limits. This method is part of the IMAP4 QUOTA extension defined in rfc2087. | python.library.imaplib#imaplib.IMAP4.getquota |
IMAP4.getquotaroot(mailbox)
Get the list of quota roots for the named mailbox. This method is part of the IMAP4 QUOTA extension defined in rfc2087. | python.library.imaplib#imaplib.IMAP4.getquotaroot |
IMAP4.list([directory[, pattern]])
List mailbox names in directory matching pattern. directory defaults to the top-level mail folder, and pattern defaults to match anything. Returned data contains a list of LIST responses. | python.library.imaplib#imaplib.IMAP4.list |
IMAP4.login(user, password)
Identify the client using a plaintext password. The password will be quoted. | python.library.imaplib#imaplib.IMAP4.login |
IMAP4.login_cram_md5(user, password)
Force use of CRAM-MD5 authentication when identifying the client to protect the password. Will only work if the server CAPABILITY response includes the phrase AUTH=CRAM-MD5. | python.library.imaplib#imaplib.IMAP4.login_cram_md5 |
IMAP4.logout()
Shutdown connection to server. Returns server BYE response. Changed in version 3.8: The method no longer ignores silently arbitrary exceptions. | python.library.imaplib#imaplib.IMAP4.logout |
IMAP4.lsub(directory='""', pattern='*')
List subscribed mailbox names in directory matching pattern. directory defaults to the top level directory and pattern defaults to match any mailbox. Returned data are tuples of message part envelope and data. | python.library.imaplib#imaplib.IMAP4.lsub |
IMAP4.myrights(mailbox)
Show my ACLs for a mailbox (i.e. the rights that I have on mailbox). | python.library.imaplib#imaplib.IMAP4.myrights |
IMAP4.namespace()
Returns IMAP namespaces as defined in RFC 2342. | python.library.imaplib#imaplib.IMAP4.namespace |
IMAP4.noop()
Send NOOP to server. | python.library.imaplib#imaplib.IMAP4.noop |
IMAP4.open(host, port, timeout=None)
Opens socket to port at host. The optional timeout parameter specifies a timeout in seconds for the connection attempt. If timeout is not given or is None, the global default socket timeout is used. Also note that if the timeout parameter is set to be zero, it will raise a ValueError to reject creating a non-blocking socket. This method is implicitly called by the IMAP4 constructor. The connection objects established by this method will be used in the IMAP4.read(), IMAP4.readline(), IMAP4.send(), and IMAP4.shutdown() methods. You may override this method. Raises an auditing event imaplib.open with arguments self, host, port. Changed in version 3.9: The timeout parameter was added. | python.library.imaplib#imaplib.IMAP4.open |
IMAP4.partial(message_num, message_part, start, length)
Fetch truncated part of a message. Returned data is a tuple of message part envelope and data. | python.library.imaplib#imaplib.IMAP4.partial |
IMAP4.PROTOCOL_VERSION
The most recent supported protocol in the CAPABILITY response from the server. | python.library.imaplib#imaplib.IMAP4.PROTOCOL_VERSION |
IMAP4.proxyauth(user)
Assume authentication as user. Allows an authorised administrator to proxy into any user’s mailbox. | python.library.imaplib#imaplib.IMAP4.proxyauth |
IMAP4.read(size)
Reads size bytes from the remote server. You may override this method. | python.library.imaplib#imaplib.IMAP4.read |
IMAP4.readline()
Reads one line from the remote server. You may override this method. | python.library.imaplib#imaplib.IMAP4.readline |
exception IMAP4.readonly
This exception is raised when a writable mailbox has its status changed by the server. This is a sub-class of IMAP4.error. Some other client now has write permission, and the mailbox will need to be re-opened to re-obtain write permission. | python.library.imaplib#imaplib.IMAP4.readonly |
IMAP4.recent()
Prompt server for an update. Returned data is None if no new messages, else value of RECENT response. | python.library.imaplib#imaplib.IMAP4.recent |
IMAP4.rename(oldmailbox, newmailbox)
Rename mailbox named oldmailbox to newmailbox. | python.library.imaplib#imaplib.IMAP4.rename |
IMAP4.response(code)
Return data for response code if received, or None. Returns the given code, instead of the usual type. | python.library.imaplib#imaplib.IMAP4.response |
IMAP4.search(charset, criterion[, ...])
Search mailbox for matching messages. charset may be None, in which case no CHARSET will be specified in the request to the server. The IMAP protocol requires that at least one criterion be specified; an exception will be raised when the server returns an error. charset must be None if the UTF8=ACCEPT capability was enabled using the enable() command. Example: # M is a connected IMAP4 instance...
typ, msgnums = M.search(None, 'FROM', '"LDJ"')
# or:
typ, msgnums = M.search(None, '(FROM "LDJ")') | python.library.imaplib#imaplib.IMAP4.search |
IMAP4.select(mailbox='INBOX', readonly=False)
Select a mailbox. Returned data is the count of messages in mailbox (EXISTS response). The default mailbox is 'INBOX'. If the readonly flag is set, modifications to the mailbox are not allowed. | python.library.imaplib#imaplib.IMAP4.select |
IMAP4.send(data)
Sends data to the remote server. You may override this method. Raises an auditing event imaplib.send with arguments self, data. | python.library.imaplib#imaplib.IMAP4.send |
IMAP4.setacl(mailbox, who, what)
Set an ACL for mailbox. The method is non-standard, but is supported by the Cyrus server. | python.library.imaplib#imaplib.IMAP4.setacl |
IMAP4.setannotation(mailbox, entry, attribute[, ...])
Set ANNOTATIONs for mailbox. The method is non-standard, but is supported by the Cyrus server. | python.library.imaplib#imaplib.IMAP4.setannotation |
IMAP4.setquota(root, limits)
Set the quota root’s resource limits. This method is part of the IMAP4 QUOTA extension defined in rfc2087. | python.library.imaplib#imaplib.IMAP4.setquota |
IMAP4.shutdown()
Close connection established in open. This method is implicitly called by IMAP4.logout(). You may override this method. | python.library.imaplib#imaplib.IMAP4.shutdown |
IMAP4.socket()
Returns socket instance used to connect to server. | python.library.imaplib#imaplib.IMAP4.socket |
IMAP4.sort(sort_criteria, charset, search_criterion[, ...])
The sort command is a variant of search with sorting semantics for the results. Returned data contains a space separated list of matching message numbers. Sort has two arguments before the search_criterion argument(s); a parenthesized list of sort_criteria, and the searching charset. Note that unlike search, the searching charset argument is mandatory. There is also a uid sort command which corresponds to sort the way that uid search corresponds to search. The sort command first searches the mailbox for messages that match the given searching criteria using the charset argument for the interpretation of strings in the searching criteria. It then returns the numbers of matching messages. This is an IMAP4rev1 extension command. | python.library.imaplib#imaplib.IMAP4.sort |
IMAP4.starttls(ssl_context=None)
Send a STARTTLS command. The ssl_context argument is optional and should be a ssl.SSLContext object. This will enable encryption on the IMAP connection. Please read Security considerations for best practices. New in version 3.2. Changed in version 3.4: The method now supports hostname check with ssl.SSLContext.check_hostname and Server Name Indication (see ssl.HAS_SNI). | python.library.imaplib#imaplib.IMAP4.starttls |
IMAP4.status(mailbox, names)
Request named status conditions for mailbox. | python.library.imaplib#imaplib.IMAP4.status |
IMAP4.store(message_set, command, flag_list)
Alters flag dispositions for messages in mailbox. command is specified by section 6.4.6 of RFC 2060 as being one of “FLAGS”, “+FLAGS”, or “-FLAGS”, optionally with a suffix of “.SILENT”. For example, to set the delete flag on all messages: typ, data = M.search(None, 'ALL')
for num in data[0].split():
M.store(num, '+FLAGS', '\\Deleted')
M.expunge()
Note Creating flags containing ‘]’ (for example: “[test]”) violates RFC 3501 (the IMAP protocol). However, imaplib has historically allowed creation of such tags, and popular IMAP servers, such as Gmail, accept and produce such flags. There are non-Python programs which also create such tags. Although it is an RFC violation and IMAP clients and servers are supposed to be strict, imaplib nonetheless continues to allow such tags to be created for backward compatibility reasons, and as of Python 3.6, handles them if they are sent from the server, since this improves real-world compatibility. | python.library.imaplib#imaplib.IMAP4.store |
IMAP4.subscribe(mailbox)
Subscribe to new mailbox. | python.library.imaplib#imaplib.IMAP4.subscribe |
IMAP4.thread(threading_algorithm, charset, search_criterion[, ...])
The thread command is a variant of search with threading semantics for the results. Returned data contains a space separated list of thread members. Thread members consist of zero or more messages numbers, delimited by spaces, indicating successive parent and child. Thread has two arguments before the search_criterion argument(s); a threading_algorithm, and the searching charset. Note that unlike search, the searching charset argument is mandatory. There is also a uid thread command which corresponds to thread the way that uid
search corresponds to search. The thread command first searches the mailbox for messages that match the given searching criteria using the charset argument for the interpretation of strings in the searching criteria. It then returns the matching messages threaded according to the specified threading algorithm. This is an IMAP4rev1 extension command. | python.library.imaplib#imaplib.IMAP4.thread |
IMAP4.uid(command, arg[, ...])
Execute command args with messages identified by UID, rather than message number. Returns response appropriate to command. At least one argument must be supplied; if none are provided, the server will return an error and an exception will be raised. | python.library.imaplib#imaplib.IMAP4.uid |
IMAP4.unselect()
imaplib.IMAP4.unselect() frees server’s resources associated with the selected mailbox and returns the server to the authenticated state. This command performs the same actions as imaplib.IMAP4.close(), except that no messages are permanently removed from the currently selected mailbox. New in version 3.9. | python.library.imaplib#imaplib.IMAP4.unselect |
IMAP4.unsubscribe(mailbox)
Unsubscribe from old mailbox. | python.library.imaplib#imaplib.IMAP4.unsubscribe |
IMAP4.utf8_enabled
Boolean value that is normally False, but is set to True if an enable() command is successfully issued for the UTF8=ACCEPT capability. New in version 3.5. | python.library.imaplib#imaplib.IMAP4.utf8_enabled |
IMAP4.xatom(name[, ...])
Allow simple extension commands notified by server in CAPABILITY response. | python.library.imaplib#imaplib.IMAP4.xatom |
class imaplib.IMAP4_SSL(host='', port=IMAP4_SSL_PORT, keyfile=None, certfile=None, ssl_context=None, timeout=None)
This is a subclass derived from IMAP4 that connects over an SSL encrypted socket (to use this class you need a socket module that was compiled with SSL support). If host is not specified, '' (the local host) is used. If port is omitted, the standard IMAP4-over-SSL port (993) is used. ssl_context is a ssl.SSLContext object which allows bundling SSL configuration options, certificates and private keys into a single (potentially long-lived) structure. Please read Security considerations for best practices. keyfile and certfile are a legacy alternative to ssl_context - they can point to PEM-formatted private key and certificate chain files for the SSL connection. Note that the keyfile/certfile parameters are mutually exclusive with ssl_context, a ValueError is raised if keyfile/certfile is provided along with ssl_context. The optional timeout parameter specifies a timeout in seconds for the connection attempt. If timeout is not given or is None, the global default socket timeout is used. Changed in version 3.3: ssl_context parameter was added. Changed in version 3.4: The class now supports hostname check with ssl.SSLContext.check_hostname and Server Name Indication (see ssl.HAS_SNI). Deprecated since version 3.6: keyfile and certfile are deprecated in favor of ssl_context. Please use ssl.SSLContext.load_cert_chain() instead, or let ssl.create_default_context() select the system’s trusted CA certificates for you. Changed in version 3.9: The optional timeout parameter was added. | python.library.imaplib#imaplib.IMAP4_SSL |
class imaplib.IMAP4_stream(command)
This is a subclass derived from IMAP4 that connects to the stdin/stdout file descriptors created by passing command to subprocess.Popen(). | python.library.imaplib#imaplib.IMAP4_stream |
imaplib.Int2AP(num)
Converts an integer into a bytes representation using characters from the set [A .. P]. | python.library.imaplib#imaplib.Int2AP |
imaplib.Internaldate2tuple(datestr)
Parse an IMAP4 INTERNALDATE string and return corresponding local time. The return value is a time.struct_time tuple or None if the string has wrong format. | python.library.imaplib#imaplib.Internaldate2tuple |
imaplib.ParseFlags(flagstr)
Converts an IMAP4 FLAGS response to a tuple of individual flags. | python.library.imaplib#imaplib.ParseFlags |
imaplib.Time2Internaldate(date_time)
Convert date_time to an IMAP4 INTERNALDATE representation. The return value is a string in the form: "DD-Mmm-YYYY HH:MM:SS
+HHMM" (including double-quotes). The date_time argument can be a number (int or float) representing seconds since epoch (as returned by time.time()), a 9-tuple representing local time an instance of time.struct_time (as returned by time.localtime()), an aware instance of datetime.datetime, or a double-quoted string. In the last case, it is assumed to already be in the correct format. | python.library.imaplib#imaplib.Time2Internaldate |
imghdr — Determine the type of an image Source code: Lib/imghdr.py The imghdr module determines the type of image contained in a file or byte stream. The imghdr module defines the following function:
imghdr.what(filename, h=None)
Tests the image data contained in the file named by filename, and returns a string describing the image type. If optional h is provided, the filename is ignored and h is assumed to contain the byte stream to test. Changed in version 3.6: Accepts a path-like object.
The following image types are recognized, as listed below with the return value from what():
Value Image format
'rgb' SGI ImgLib Files
'gif' GIF 87a and 89a Files
'pbm' Portable Bitmap Files
'pgm' Portable Graymap Files
'ppm' Portable Pixmap Files
'tiff' TIFF Files
'rast' Sun Raster Files
'xbm' X Bitmap Files
'jpeg' JPEG data in JFIF or Exif formats
'bmp' BMP files
'png' Portable Network Graphics
'webp' WebP files
'exr' OpenEXR Files New in version 3.5: The exr and webp formats were added. You can extend the list of file types imghdr can recognize by appending to this variable:
imghdr.tests
A list of functions performing the individual tests. Each function takes two arguments: the byte-stream and an open file-like object. When what() is called with a byte-stream, the file-like object will be None. The test function should return a string describing the image type if the test succeeded, or None if it failed.
Example: >>> import imghdr
>>> imghdr.what('bass.gif')
'gif' | python.library.imghdr |
imghdr.tests
A list of functions performing the individual tests. Each function takes two arguments: the byte-stream and an open file-like object. When what() is called with a byte-stream, the file-like object will be None. The test function should return a string describing the image type if the test succeeded, or None if it failed. | python.library.imghdr#imghdr.tests |
imghdr.what(filename, h=None)
Tests the image data contained in the file named by filename, and returns a string describing the image type. If optional h is provided, the filename is ignored and h is assumed to contain the byte stream to test. Changed in version 3.6: Accepts a path-like object. | python.library.imghdr#imghdr.what |
exception ImportError
Raised when the import statement has troubles trying to load a module. Also raised when the “from list” in from ... import has a name that cannot be found. The name and path attributes can be set using keyword-only arguments to the constructor. When set they represent the name of the module that was attempted to be imported and the path to any file which triggered the exception, respectively. Changed in version 3.3: Added the name and path attributes. | python.library.exceptions#ImportError |
importlib — The implementation of import New in version 3.1. Source code: Lib/importlib/__init__.py Introduction The purpose of the importlib package is two-fold. One is to provide the implementation of the import statement (and thus, by extension, the __import__() function) in Python source code. This provides an implementation of import which is portable to any Python interpreter. This also provides an implementation which is easier to comprehend than one implemented in a programming language other than Python. Two, the components to implement import are exposed in this package, making it easier for users to create their own custom objects (known generically as an importer) to participate in the import process. See also The import statement
The language reference for the import statement. Packages specification
Original specification of packages. Some semantics have changed since the writing of this document (e.g. redirecting based on None in sys.modules).
The __import__() function
The import statement is syntactic sugar for this function. PEP 235
Import on Case-Insensitive Platforms PEP 263
Defining Python Source Code Encodings PEP 302
New Import Hooks PEP 328
Imports: Multi-Line and Absolute/Relative PEP 366
Main module explicit relative imports PEP 420
Implicit namespace packages PEP 451
A ModuleSpec Type for the Import System PEP 488
Elimination of PYO files PEP 489
Multi-phase extension module initialization PEP 552
Deterministic pycs PEP 3120
Using UTF-8 as the Default Source Encoding PEP 3147
PYC Repository Directories Functions
importlib.__import__(name, globals=None, locals=None, fromlist=(), level=0)
An implementation of the built-in __import__() function. Note Programmatic importing of modules should use import_module() instead of this function.
importlib.import_module(name, package=None)
Import a module. The name argument specifies what module to import in absolute or relative terms (e.g. either pkg.mod or ..mod). If the name is specified in relative terms, then the package argument must be set to the name of the package which is to act as the anchor for resolving the package name (e.g. import_module('..mod', 'pkg.subpkg') will import pkg.mod). The import_module() function acts as a simplifying wrapper around importlib.__import__(). This means all semantics of the function are derived from importlib.__import__(). The most important difference between these two functions is that import_module() returns the specified package or module (e.g. pkg.mod), while __import__() returns the top-level package or module (e.g. pkg). If you are dynamically importing a module that was created since the interpreter began execution (e.g., created a Python source file), you may need to call invalidate_caches() in order for the new module to be noticed by the import system. Changed in version 3.3: Parent packages are automatically imported.
importlib.find_loader(name, path=None)
Find the loader for a module, optionally within the specified path. If the module is in sys.modules, then sys.modules[name].__loader__ is returned (unless the loader would be None or is not set, in which case ValueError is raised). Otherwise a search using sys.meta_path is done. None is returned if no loader is found. A dotted name does not have its parents implicitly imported as that requires loading them and that may not be desired. To properly import a submodule you will need to import all parent packages of the submodule and use the correct argument to path. New in version 3.3. Changed in version 3.4: If __loader__ is not set, raise ValueError, just like when the attribute is set to None. Deprecated since version 3.4: Use importlib.util.find_spec() instead.
importlib.invalidate_caches()
Invalidate the internal caches of finders stored at sys.meta_path. If a finder implements invalidate_caches() then it will be called to perform the invalidation. This function should be called if any modules are created/installed while your program is running to guarantee all finders will notice the new module’s existence. New in version 3.3.
importlib.reload(module)
Reload a previously imported module. The argument must be a module object, so it must have been successfully imported before. This is useful if you have edited the module source file using an external editor and want to try out the new version without leaving the Python interpreter. The return value is the module object (which can be different if re-importing causes a different object to be placed in sys.modules). When reload() is executed: Python module’s code is recompiled and the module-level code re-executed, defining a new set of objects which are bound to names in the module’s dictionary by reusing the loader which originally loaded the module. The init function of extension modules is not called a second time. As with all other objects in Python the old objects are only reclaimed after their reference counts drop to zero. The names in the module namespace are updated to point to any new or changed objects. Other references to the old objects (such as names external to the module) are not rebound to refer to the new objects and must be updated in each namespace where they occur if that is desired. There are a number of other caveats: When a module is reloaded, its dictionary (containing the module’s global variables) is retained. Redefinitions of names will override the old definitions, so this is generally not a problem. If the new version of a module does not define a name that was defined by the old version, the old definition remains. This feature can be used to the module’s advantage if it maintains a global table or cache of objects — with a try statement it can test for the table’s presence and skip its initialization if desired: try:
cache
except NameError:
cache = {}
It is generally not very useful to reload built-in or dynamically loaded modules. Reloading sys, __main__, builtins and other key modules is not recommended. In many cases extension modules are not designed to be initialized more than once, and may fail in arbitrary ways when reloaded. If a module imports objects from another module using from … import …, calling reload() for the other module does not redefine the objects imported from it — one way around this is to re-execute the from statement, another is to use import and qualified names (module.name) instead. If a module instantiates instances of a class, reloading the module that defines the class does not affect the method definitions of the instances — they continue to use the old class definition. The same is true for derived classes. New in version 3.4. Changed in version 3.7: ModuleNotFoundError is raised when the module being reloaded lacks a ModuleSpec.
importlib.abc – Abstract base classes related to import Source code: Lib/importlib/abc.py The importlib.abc module contains all of the core abstract base classes used by import. Some subclasses of the core abstract base classes are also provided to help in implementing the core ABCs. ABC hierarchy: object
+-- Finder (deprecated)
| +-- MetaPathFinder
| +-- PathEntryFinder
+-- Loader
+-- ResourceLoader --------+
+-- InspectLoader |
+-- ExecutionLoader --+
+-- FileLoader
+-- SourceLoader
class importlib.abc.Finder
An abstract base class representing a finder. Deprecated since version 3.3: Use MetaPathFinder or PathEntryFinder instead.
abstractmethod find_module(fullname, path=None)
An abstract method for finding a loader for the specified module. Originally specified in PEP 302, this method was meant for use in sys.meta_path and in the path-based import subsystem. Changed in version 3.4: Returns None when called instead of raising NotImplementedError.
class importlib.abc.MetaPathFinder
An abstract base class representing a meta path finder. For compatibility, this is a subclass of Finder. New in version 3.3.
find_spec(fullname, path, target=None)
An abstract method for finding a spec for the specified module. If this is a top-level import, path will be None. Otherwise, this is a search for a subpackage or module and path will be the value of __path__ from the parent package. If a spec cannot be found, None is returned. When passed in, target is a module object that the finder may use to make a more educated guess about what spec to return. importlib.util.spec_from_loader() may be useful for implementing concrete MetaPathFinders. New in version 3.4.
find_module(fullname, path)
A legacy method for finding a loader for the specified module. If this is a top-level import, path will be None. Otherwise, this is a search for a subpackage or module and path will be the value of __path__ from the parent package. If a loader cannot be found, None is returned. If find_spec() is defined, backwards-compatible functionality is provided. Changed in version 3.4: Returns None when called instead of raising NotImplementedError. Can use find_spec() to provide functionality. Deprecated since version 3.4: Use find_spec() instead.
invalidate_caches()
An optional method which, when called, should invalidate any internal cache used by the finder. Used by importlib.invalidate_caches() when invalidating the caches of all finders on sys.meta_path. Changed in version 3.4: Returns None when called instead of NotImplemented.
class importlib.abc.PathEntryFinder
An abstract base class representing a path entry finder. Though it bears some similarities to MetaPathFinder, PathEntryFinder is meant for use only within the path-based import subsystem provided by PathFinder. This ABC is a subclass of Finder for compatibility reasons only. New in version 3.3.
find_spec(fullname, target=None)
An abstract method for finding a spec for the specified module. The finder will search for the module only within the path entry to which it is assigned. If a spec cannot be found, None is returned. When passed in, target is a module object that the finder may use to make a more educated guess about what spec to return. importlib.util.spec_from_loader() may be useful for implementing concrete PathEntryFinders. New in version 3.4.
find_loader(fullname)
A legacy method for finding a loader for the specified module. Returns a 2-tuple of (loader, portion) where portion is a sequence of file system locations contributing to part of a namespace package. The loader may be None while specifying portion to signify the contribution of the file system locations to a namespace package. An empty list can be used for portion to signify the loader is not part of a namespace package. If loader is None and portion is the empty list then no loader or location for a namespace package were found (i.e. failure to find anything for the module). If find_spec() is defined then backwards-compatible functionality is provided. Changed in version 3.4: Returns (None, []) instead of raising NotImplementedError. Uses find_spec() when available to provide functionality. Deprecated since version 3.4: Use find_spec() instead.
find_module(fullname)
A concrete implementation of Finder.find_module() which is equivalent to self.find_loader(fullname)[0]. Deprecated since version 3.4: Use find_spec() instead.
invalidate_caches()
An optional method which, when called, should invalidate any internal cache used by the finder. Used by PathFinder.invalidate_caches() when invalidating the caches of all cached finders.
class importlib.abc.Loader
An abstract base class for a loader. See PEP 302 for the exact definition for a loader. Loaders that wish to support resource reading should implement a get_resource_reader(fullname) method as specified by importlib.abc.ResourceReader. Changed in version 3.7: Introduced the optional get_resource_reader() method.
create_module(spec)
A method that returns the module object to use when importing a module. This method may return None, indicating that default module creation semantics should take place. New in version 3.4. Changed in version 3.5: Starting in Python 3.6, this method will not be optional when exec_module() is defined.
exec_module(module)
An abstract method that executes the module in its own namespace when a module is imported or reloaded. The module should already be initialized when exec_module() is called. When this method exists, create_module() must be defined. New in version 3.4. Changed in version 3.6: create_module() must also be defined.
load_module(fullname)
A legacy method for loading a module. If the module cannot be loaded, ImportError is raised, otherwise the loaded module is returned. If the requested module already exists in sys.modules, that module should be used and reloaded. Otherwise the loader should create a new module and insert it into sys.modules before any loading begins, to prevent recursion from the import. If the loader inserted a module and the load fails, it must be removed by the loader from sys.modules; modules already in sys.modules before the loader began execution should be left alone (see importlib.util.module_for_loader()). The loader should set several attributes on the module. (Note that some of these attributes can change when a module is reloaded):
__name__
The name of the module.
__file__
The path to where the module data is stored (not set for built-in modules).
__cached__
The path to where a compiled version of the module is/should be stored (not set when the attribute would be inappropriate).
__path__
A list of strings specifying the search path within a package. This attribute is not set on modules.
__package__
The fully-qualified name of the package under which the module was loaded as a submodule (or the empty string for top-level modules). For packages, it is the same as __name__. The importlib.util.module_for_loader() decorator can handle the details for __package__.
__loader__
The loader used to load the module. The importlib.util.module_for_loader() decorator can handle the details for __package__. When exec_module() is available then backwards-compatible functionality is provided. Changed in version 3.4: Raise ImportError when called instead of NotImplementedError. Functionality provided when exec_module() is available. Deprecated since version 3.4: The recommended API for loading a module is exec_module() (and create_module()). Loaders should implement it instead of load_module(). The import machinery takes care of all the other responsibilities of load_module() when exec_module() is implemented.
module_repr(module)
A legacy method which when implemented calculates and returns the given module’s repr, as a string. The module type’s default repr() will use the result of this method as appropriate. New in version 3.3. Changed in version 3.4: Made optional instead of an abstractmethod. Deprecated since version 3.4: The import machinery now takes care of this automatically.
class importlib.abc.ResourceReader
Superseded by TraversableReader An abstract base class to provide the ability to read resources. From the perspective of this ABC, a resource is a binary artifact that is shipped within a package. Typically this is something like a data file that lives next to the __init__.py file of the package. The purpose of this class is to help abstract out the accessing of such data files so that it does not matter if the package and its data file(s) are stored in a e.g. zip file versus on the file system. For any of methods of this class, a resource argument is expected to be a path-like object which represents conceptually just a file name. This means that no subdirectory paths should be included in the resource argument. This is because the location of the package the reader is for, acts as the “directory”. Hence the metaphor for directories and file names is packages and resources, respectively. This is also why instances of this class are expected to directly correlate to a specific package (instead of potentially representing multiple packages or a module). Loaders that wish to support resource reading are expected to provide a method called get_resource_reader(fullname) which returns an object implementing this ABC’s interface. If the module specified by fullname is not a package, this method should return None. An object compatible with this ABC should only be returned when the specified module is a package. New in version 3.7.
abstractmethod open_resource(resource)
Returns an opened, file-like object for binary reading of the resource. If the resource cannot be found, FileNotFoundError is raised.
abstractmethod resource_path(resource)
Returns the file system path to the resource. If the resource does not concretely exist on the file system, raise FileNotFoundError.
abstractmethod is_resource(name)
Returns True if the named name is considered a resource. FileNotFoundError is raised if name does not exist.
abstractmethod contents()
Returns an iterable of strings over the contents of the package. Do note that it is not required that all names returned by the iterator be actual resources, e.g. it is acceptable to return names for which is_resource() would be false. Allowing non-resource names to be returned is to allow for situations where how a package and its resources are stored are known a priori and the non-resource names would be useful. For instance, returning subdirectory names is allowed so that when it is known that the package and resources are stored on the file system then those subdirectory names can be used directly. The abstract method returns an iterable of no items.
class importlib.abc.ResourceLoader
An abstract base class for a loader which implements the optional PEP 302 protocol for loading arbitrary resources from the storage back-end. Deprecated since version 3.7: This ABC is deprecated in favour of supporting resource loading through importlib.abc.ResourceReader.
abstractmethod get_data(path)
An abstract method to return the bytes for the data located at path. Loaders that have a file-like storage back-end that allows storing arbitrary data can implement this abstract method to give direct access to the data stored. OSError is to be raised if the path cannot be found. The path is expected to be constructed using a module’s __file__ attribute or an item from a package’s __path__. Changed in version 3.4: Raises OSError instead of NotImplementedError.
class importlib.abc.InspectLoader
An abstract base class for a loader which implements the optional PEP 302 protocol for loaders that inspect modules.
get_code(fullname)
Return the code object for a module, or None if the module does not have a code object (as would be the case, for example, for a built-in module). Raise an ImportError if loader cannot find the requested module. Note While the method has a default implementation, it is suggested that it be overridden if possible for performance. Changed in version 3.4: No longer abstract and a concrete implementation is provided.
abstractmethod get_source(fullname)
An abstract method to return the source of a module. It is returned as a text string using universal newlines, translating all recognized line separators into '\n' characters. Returns None if no source is available (e.g. a built-in module). Raises ImportError if the loader cannot find the module specified. Changed in version 3.4: Raises ImportError instead of NotImplementedError.
is_package(fullname)
An abstract method to return a true value if the module is a package, a false value otherwise. ImportError is raised if the loader cannot find the module. Changed in version 3.4: Raises ImportError instead of NotImplementedError.
static source_to_code(data, path='<string>')
Create a code object from Python source. The data argument can be whatever the compile() function supports (i.e. string or bytes). The path argument should be the “path” to where the source code originated from, which can be an abstract concept (e.g. location in a zip file). With the subsequent code object one can execute it in a module by running exec(code, module.__dict__). New in version 3.4. Changed in version 3.5: Made the method static.
exec_module(module)
Implementation of Loader.exec_module(). New in version 3.4.
load_module(fullname)
Implementation of Loader.load_module(). Deprecated since version 3.4: use exec_module() instead.
class importlib.abc.ExecutionLoader
An abstract base class which inherits from InspectLoader that, when implemented, helps a module to be executed as a script. The ABC represents an optional PEP 302 protocol.
abstractmethod get_filename(fullname)
An abstract method that is to return the value of __file__ for the specified module. If no path is available, ImportError is raised. If source code is available, then the method should return the path to the source file, regardless of whether a bytecode was used to load the module. Changed in version 3.4: Raises ImportError instead of NotImplementedError.
class importlib.abc.FileLoader(fullname, path)
An abstract base class which inherits from ResourceLoader and ExecutionLoader, providing concrete implementations of ResourceLoader.get_data() and ExecutionLoader.get_filename(). The fullname argument is a fully resolved name of the module the loader is to handle. The path argument is the path to the file for the module. New in version 3.3.
name
The name of the module the loader can handle.
path
Path to the file of the module.
load_module(fullname)
Calls super’s load_module(). Deprecated since version 3.4: Use Loader.exec_module() instead.
abstractmethod get_filename(fullname)
Returns path.
abstractmethod get_data(path)
Reads path as a binary file and returns the bytes from it.
class importlib.abc.SourceLoader
An abstract base class for implementing source (and optionally bytecode) file loading. The class inherits from both ResourceLoader and ExecutionLoader, requiring the implementation of: ResourceLoader.get_data()
ExecutionLoader.get_filename()
Should only return the path to the source file; sourceless loading is not supported. The abstract methods defined by this class are to add optional bytecode file support. Not implementing these optional methods (or causing them to raise NotImplementedError) causes the loader to only work with source code. Implementing the methods allows the loader to work with source and bytecode files; it does not allow for sourceless loading where only bytecode is provided. Bytecode files are an optimization to speed up loading by removing the parsing step of Python’s compiler, and so no bytecode-specific API is exposed.
path_stats(path)
Optional abstract method which returns a dict containing metadata about the specified path. Supported dictionary keys are:
'mtime' (mandatory): an integer or floating-point number representing the modification time of the source code;
'size' (optional): the size in bytes of the source code. Any other keys in the dictionary are ignored, to allow for future extensions. If the path cannot be handled, OSError is raised. New in version 3.3. Changed in version 3.4: Raise OSError instead of NotImplementedError.
path_mtime(path)
Optional abstract method which returns the modification time for the specified path. Deprecated since version 3.3: This method is deprecated in favour of path_stats(). You don’t have to implement it, but it is still available for compatibility purposes. Raise OSError if the path cannot be handled. Changed in version 3.4: Raise OSError instead of NotImplementedError.
set_data(path, data)
Optional abstract method which writes the specified bytes to a file path. Any intermediate directories which do not exist are to be created automatically. When writing to the path fails because the path is read-only (errno.EACCES/PermissionError), do not propagate the exception. Changed in version 3.4: No longer raises NotImplementedError when called.
get_code(fullname)
Concrete implementation of InspectLoader.get_code().
exec_module(module)
Concrete implementation of Loader.exec_module(). New in version 3.4.
load_module(fullname)
Concrete implementation of Loader.load_module(). Deprecated since version 3.4: Use exec_module() instead.
get_source(fullname)
Concrete implementation of InspectLoader.get_source().
is_package(fullname)
Concrete implementation of InspectLoader.is_package(). A module is determined to be a package if its file path (as provided by ExecutionLoader.get_filename()) is a file named __init__ when the file extension is removed and the module name itself does not end in __init__.
class importlib.abc.Traversable
An object with a subset of pathlib.Path methods suitable for traversing directories and opening files. New in version 3.9.
class importlib.abc.TraversableReader
An abstract base class for resource readers capable of serving the files interface. Subclasses ResourceReader and provides concrete implementations of the ResourceReader’s abstract methods. Therefore, any loader supplying TraversableReader also supplies ResourceReader. New in version 3.9.
importlib.resources – Resources Source code: Lib/importlib/resources.py New in version 3.7. This module leverages Python’s import system to provide access to resources within packages. If you can import a package, you can access resources within that package. Resources can be opened or read, in either binary or text mode. Resources are roughly akin to files inside directories, though it’s important to keep in mind that this is just a metaphor. Resources and packages do not have to exist as physical files and directories on the file system. Note This module provides functionality similar to pkg_resources Basic Resource Access without the performance overhead of that package. This makes reading resources included in packages easier, with more stable and consistent semantics. The standalone backport of this module provides more information on using importlib.resources and migrating from pkg_resources to importlib.resources. Loaders that wish to support resource reading should implement a get_resource_reader(fullname) method as specified by importlib.abc.ResourceReader. The following types are defined.
importlib.resources.Package
The Package type is defined as Union[str, ModuleType]. This means that where the function describes accepting a Package, you can pass in either a string or a module. Module objects must have a resolvable __spec__.submodule_search_locations that is not None.
importlib.resources.Resource
This type describes the resource names passed into the various functions in this package. This is defined as Union[str, os.PathLike].
The following functions are available.
importlib.resources.files(package)
Returns an importlib.resources.abc.Traversable object representing the resource container for the package (think directory) and its resources (think files). A Traversable may contain other containers (think subdirectories). package is either a name or a module object which conforms to the Package requirements. New in version 3.9.
importlib.resources.as_file(traversable)
Given a importlib.resources.abc.Traversable object representing a file, typically from importlib.resources.files(), return a context manager for use in a with statement. The context manager provides a pathlib.Path object. Exiting the context manager cleans up any temporary file created when the resource was extracted from e.g. a zip file. Use as_file when the Traversable methods (read_text, etc) are insufficient and an actual file on the file system is required. New in version 3.9.
importlib.resources.open_binary(package, resource)
Open for binary reading the resource within package. package is either a name or a module object which conforms to the Package requirements. resource is the name of the resource to open within package; it may not contain path separators and it may not have sub-resources (i.e. it cannot be a directory). This function returns a typing.BinaryIO instance, a binary I/O stream open for reading.
importlib.resources.open_text(package, resource, encoding='utf-8', errors='strict')
Open for text reading the resource within package. By default, the resource is opened for reading as UTF-8. package is either a name or a module object which conforms to the Package requirements. resource is the name of the resource to open within package; it may not contain path separators and it may not have sub-resources (i.e. it cannot be a directory). encoding and errors have the same meaning as with built-in open(). This function returns a typing.TextIO instance, a text I/O stream open for reading.
importlib.resources.read_binary(package, resource)
Read and return the contents of the resource within package as bytes. package is either a name or a module object which conforms to the Package requirements. resource is the name of the resource to open within package; it may not contain path separators and it may not have sub-resources (i.e. it cannot be a directory). This function returns the contents of the resource as bytes.
importlib.resources.read_text(package, resource, encoding='utf-8', errors='strict')
Read and return the contents of resource within package as a str. By default, the contents are read as strict UTF-8. package is either a name or a module object which conforms to the Package requirements. resource is the name of the resource to open within package; it may not contain path separators and it may not have sub-resources (i.e. it cannot be a directory). encoding and errors have the same meaning as with built-in open(). This function returns the contents of the resource as str.
importlib.resources.path(package, resource)
Return the path to the resource as an actual file system path. This function returns a context manager for use in a with statement. The context manager provides a pathlib.Path object. Exiting the context manager cleans up any temporary file created when the resource needs to be extracted from e.g. a zip file. package is either a name or a module object which conforms to the Package requirements. resource is the name of the resource to open within package; it may not contain path separators and it may not have sub-resources (i.e. it cannot be a directory).
importlib.resources.is_resource(package, name)
Return True if there is a resource named name in the package, otherwise False. Remember that directories are not resources! package is either a name or a module object which conforms to the Package requirements.
importlib.resources.contents(package)
Return an iterable over the named items within the package. The iterable returns str resources (e.g. files) and non-resources (e.g. directories). The iterable does not recurse into subdirectories. package is either a name or a module object which conforms to the Package requirements.
importlib.machinery – Importers and path hooks Source code: Lib/importlib/machinery.py This module contains the various objects that help import find and load modules.
importlib.machinery.SOURCE_SUFFIXES
A list of strings representing the recognized file suffixes for source modules. New in version 3.3.
importlib.machinery.DEBUG_BYTECODE_SUFFIXES
A list of strings representing the file suffixes for non-optimized bytecode modules. New in version 3.3. Deprecated since version 3.5: Use BYTECODE_SUFFIXES instead.
importlib.machinery.OPTIMIZED_BYTECODE_SUFFIXES
A list of strings representing the file suffixes for optimized bytecode modules. New in version 3.3. Deprecated since version 3.5: Use BYTECODE_SUFFIXES instead.
importlib.machinery.BYTECODE_SUFFIXES
A list of strings representing the recognized file suffixes for bytecode modules (including the leading dot). New in version 3.3. Changed in version 3.5: The value is no longer dependent on __debug__.
importlib.machinery.EXTENSION_SUFFIXES
A list of strings representing the recognized file suffixes for extension modules. New in version 3.3.
importlib.machinery.all_suffixes()
Returns a combined list of strings representing all file suffixes for modules recognized by the standard import machinery. This is a helper for code which simply needs to know if a filesystem path potentially refers to a module without needing any details on the kind of module (for example, inspect.getmodulename()). New in version 3.3.
class importlib.machinery.BuiltinImporter
An importer for built-in modules. All known built-in modules are listed in sys.builtin_module_names. This class implements the importlib.abc.MetaPathFinder and importlib.abc.InspectLoader ABCs. Only class methods are defined by this class to alleviate the need for instantiation. Changed in version 3.5: As part of PEP 489, the builtin importer now implements Loader.create_module() and Loader.exec_module()
class importlib.machinery.FrozenImporter
An importer for frozen modules. This class implements the importlib.abc.MetaPathFinder and importlib.abc.InspectLoader ABCs. Only class methods are defined by this class to alleviate the need for instantiation. Changed in version 3.4: Gained create_module() and exec_module() methods.
class importlib.machinery.WindowsRegistryFinder
Finder for modules declared in the Windows registry. This class implements the importlib.abc.MetaPathFinder ABC. Only class methods are defined by this class to alleviate the need for instantiation. New in version 3.3. Deprecated since version 3.6: Use site configuration instead. Future versions of Python may not enable this finder by default.
class importlib.machinery.PathFinder
A Finder for sys.path and package __path__ attributes. This class implements the importlib.abc.MetaPathFinder ABC. Only class methods are defined by this class to alleviate the need for instantiation.
classmethod find_spec(fullname, path=None, target=None)
Class method that attempts to find a spec for the module specified by fullname on sys.path or, if defined, on path. For each path entry that is searched, sys.path_importer_cache is checked. If a non-false object is found then it is used as the path entry finder to look for the module being searched for. If no entry is found in sys.path_importer_cache, then sys.path_hooks is searched for a finder for the path entry and, if found, is stored in sys.path_importer_cache along with being queried about the module. If no finder is ever found then None is both stored in the cache and returned. New in version 3.4. Changed in version 3.5: If the current working directory – represented by an empty string – is no longer valid then None is returned but no value is cached in sys.path_importer_cache.
classmethod find_module(fullname, path=None)
A legacy wrapper around find_spec(). Deprecated since version 3.4: Use find_spec() instead.
classmethod invalidate_caches()
Calls importlib.abc.PathEntryFinder.invalidate_caches() on all finders stored in sys.path_importer_cache that define the method. Otherwise entries in sys.path_importer_cache set to None are deleted. Changed in version 3.7: Entries of None in sys.path_importer_cache are deleted.
Changed in version 3.4: Calls objects in sys.path_hooks with the current working directory for '' (i.e. the empty string).
class importlib.machinery.FileFinder(path, *loader_details)
A concrete implementation of importlib.abc.PathEntryFinder which caches results from the file system. The path argument is the directory for which the finder is in charge of searching. The loader_details argument is a variable number of 2-item tuples each containing a loader and a sequence of file suffixes the loader recognizes. The loaders are expected to be callables which accept two arguments of the module’s name and the path to the file found. The finder will cache the directory contents as necessary, making stat calls for each module search to verify the cache is not outdated. Because cache staleness relies upon the granularity of the operating system’s state information of the file system, there is a potential race condition of searching for a module, creating a new file, and then searching for the module the new file represents. If the operations happen fast enough to fit within the granularity of stat calls, then the module search will fail. To prevent this from happening, when you create a module dynamically, make sure to call importlib.invalidate_caches(). New in version 3.3.
path
The path the finder will search in.
find_spec(fullname, target=None)
Attempt to find the spec to handle fullname within path. New in version 3.4.
find_loader(fullname)
Attempt to find the loader to handle fullname within path.
invalidate_caches()
Clear out the internal cache.
classmethod path_hook(*loader_details)
A class method which returns a closure for use on sys.path_hooks. An instance of FileFinder is returned by the closure using the path argument given to the closure directly and loader_details indirectly. If the argument to the closure is not an existing directory, ImportError is raised.
class importlib.machinery.SourceFileLoader(fullname, path)
A concrete implementation of importlib.abc.SourceLoader by subclassing importlib.abc.FileLoader and providing some concrete implementations of other methods. New in version 3.3.
name
The name of the module that this loader will handle.
path
The path to the source file.
is_package(fullname)
Return True if path appears to be for a package.
path_stats(path)
Concrete implementation of importlib.abc.SourceLoader.path_stats().
set_data(path, data)
Concrete implementation of importlib.abc.SourceLoader.set_data().
load_module(name=None)
Concrete implementation of importlib.abc.Loader.load_module() where specifying the name of the module to load is optional. Deprecated since version 3.6: Use importlib.abc.Loader.exec_module() instead.
class importlib.machinery.SourcelessFileLoader(fullname, path)
A concrete implementation of importlib.abc.FileLoader which can import bytecode files (i.e. no source code files exist). Please note that direct use of bytecode files (and thus not source code files) inhibits your modules from being usable by all Python implementations or new versions of Python which change the bytecode format. New in version 3.3.
name
The name of the module the loader will handle.
path
The path to the bytecode file.
is_package(fullname)
Determines if the module is a package based on path.
get_code(fullname)
Returns the code object for name created from path.
get_source(fullname)
Returns None as bytecode files have no source when this loader is used.
load_module(name=None)
Concrete implementation of importlib.abc.Loader.load_module() where specifying the name of the module to load is optional. Deprecated since version 3.6: Use importlib.abc.Loader.exec_module() instead.
class importlib.machinery.ExtensionFileLoader(fullname, path)
A concrete implementation of importlib.abc.ExecutionLoader for extension modules. The fullname argument specifies the name of the module the loader is to support. The path argument is the path to the extension module’s file. New in version 3.3.
name
Name of the module the loader supports.
path
Path to the extension module.
create_module(spec)
Creates the module object from the given specification in accordance with PEP 489. New in version 3.5.
exec_module(module)
Initializes the given module object in accordance with PEP 489. New in version 3.5.
is_package(fullname)
Returns True if the file path points to a package’s __init__ module based on EXTENSION_SUFFIXES.
get_code(fullname)
Returns None as extension modules lack a code object.
get_source(fullname)
Returns None as extension modules do not have source code.
get_filename(fullname)
Returns path. New in version 3.4.
class importlib.machinery.ModuleSpec(name, loader, *, origin=None, loader_state=None, is_package=None)
A specification for a module’s import-system-related state. This is typically exposed as the module’s __spec__ attribute. In the descriptions below, the names in parentheses give the corresponding attribute available directly on the module object. E.g. module.__spec__.origin == module.__file__. Note however that while the values are usually equivalent, they can differ since there is no synchronization between the two objects. Thus it is possible to update the module’s __path__ at runtime, and this will not be automatically reflected in __spec__.submodule_search_locations. New in version 3.4.
name
(__name__) A string for the fully-qualified name of the module.
loader
(__loader__) The Loader that should be used when loading the module. Finders should always set this.
origin
(__file__) Name of the place from which the module is loaded, e.g. “builtin” for built-in modules and the filename for modules loaded from source. Normally “origin” should be set, but it may be None (the default) which indicates it is unspecified (e.g. for namespace packages).
submodule_search_locations
(__path__) List of strings for where to find submodules, if a package (None otherwise).
loader_state
Container of extra module-specific data for use during loading (or None).
cached
(__cached__) String for where the compiled module should be stored (or None).
parent
(__package__) (Read-only) The fully-qualified name of the package under which the module should be loaded as a submodule (or the empty string for top-level modules). For packages, it is the same as __name__.
has_location
Boolean indicating whether or not the module’s “origin” attribute refers to a loadable location.
importlib.util – Utility code for importers Source code: Lib/importlib/util.py This module contains the various objects that help in the construction of an importer.
importlib.util.MAGIC_NUMBER
The bytes which represent the bytecode version number. If you need help with loading/writing bytecode then consider importlib.abc.SourceLoader. New in version 3.4.
importlib.util.cache_from_source(path, debug_override=None, *, optimization=None)
Return the PEP 3147/PEP 488 path to the byte-compiled file associated with the source path. For example, if path is /foo/bar/baz.py the return value would be /foo/bar/__pycache__/baz.cpython-32.pyc for Python 3.2. The cpython-32 string comes from the current magic tag (see get_tag(); if sys.implementation.cache_tag is not defined then NotImplementedError will be raised). The optimization parameter is used to specify the optimization level of the bytecode file. An empty string represents no optimization, so /foo/bar/baz.py with an optimization of '' will result in a bytecode path of /foo/bar/__pycache__/baz.cpython-32.pyc. None causes the interpreter’s optimization level to be used. Any other value’s string representation is used, so /foo/bar/baz.py with an optimization of 2 will lead to the bytecode path of /foo/bar/__pycache__/baz.cpython-32.opt-2.pyc. The string representation of optimization can only be alphanumeric, else ValueError is raised. The debug_override parameter is deprecated and can be used to override the system’s value for __debug__. A True value is the equivalent of setting optimization to the empty string. A False value is the same as setting optimization to 1. If both debug_override an optimization are not None then TypeError is raised. New in version 3.4. Changed in version 3.5: The optimization parameter was added and the debug_override parameter was deprecated. Changed in version 3.6: Accepts a path-like object.
importlib.util.source_from_cache(path)
Given the path to a PEP 3147 file name, return the associated source code file path. For example, if path is /foo/bar/__pycache__/baz.cpython-32.pyc the returned path would be /foo/bar/baz.py. path need not exist, however if it does not conform to PEP 3147 or PEP 488 format, a ValueError is raised. If sys.implementation.cache_tag is not defined, NotImplementedError is raised. New in version 3.4. Changed in version 3.6: Accepts a path-like object.
importlib.util.decode_source(source_bytes)
Decode the given bytes representing source code and return it as a string with universal newlines (as required by importlib.abc.InspectLoader.get_source()). New in version 3.4.
importlib.util.resolve_name(name, package)
Resolve a relative module name to an absolute one. If name has no leading dots, then name is simply returned. This allows for usage such as importlib.util.resolve_name('sys', __spec__.parent) without doing a check to see if the package argument is needed. ImportError is raised if name is a relative module name but package is a false value (e.g. None or the empty string). ImportError is also raised a relative name would escape its containing package (e.g. requesting ..bacon from within the spam package). New in version 3.3. Changed in version 3.9: To improve consistency with import statements, raise ImportError instead of ValueError for invalid relative import attempts.
importlib.util.find_spec(name, package=None)
Find the spec for a module, optionally relative to the specified package name. If the module is in sys.modules, then sys.modules[name].__spec__ is returned (unless the spec would be None or is not set, in which case ValueError is raised). Otherwise a search using sys.meta_path is done. None is returned if no spec is found. If name is for a submodule (contains a dot), the parent module is automatically imported. name and package work the same as for import_module(). New in version 3.4. Changed in version 3.7: Raises ModuleNotFoundError instead of AttributeError if package is in fact not a package (i.e. lacks a __path__ attribute).
importlib.util.module_from_spec(spec)
Create a new module based on spec and spec.loader.create_module. If spec.loader.create_module does not return None, then any pre-existing attributes will not be reset. Also, no AttributeError will be raised if triggered while accessing spec or setting an attribute on the module. This function is preferred over using types.ModuleType to create a new module as spec is used to set as many import-controlled attributes on the module as possible. New in version 3.5.
@importlib.util.module_for_loader
A decorator for importlib.abc.Loader.load_module() to handle selecting the proper module object to load with. The decorated method is expected to have a call signature taking two positional arguments (e.g. load_module(self, module)) for which the second argument will be the module object to be used by the loader. Note that the decorator will not work on static methods because of the assumption of two arguments. The decorated method will take in the name of the module to be loaded as expected for a loader. If the module is not found in sys.modules then a new one is constructed. Regardless of where the module came from, __loader__ set to self and __package__ is set based on what importlib.abc.InspectLoader.is_package() returns (if available). These attributes are set unconditionally to support reloading. If an exception is raised by the decorated method and a module was added to sys.modules, then the module will be removed to prevent a partially initialized module from being in left in sys.modules. If the module was already in sys.modules then it is left alone. Changed in version 3.3: __loader__ and __package__ are automatically set (when possible). Changed in version 3.4: Set __name__, __loader__ __package__ unconditionally to support reloading. Deprecated since version 3.4: The import machinery now directly performs all the functionality provided by this function.
@importlib.util.set_loader
A decorator for importlib.abc.Loader.load_module() to set the __loader__ attribute on the returned module. If the attribute is already set the decorator does nothing. It is assumed that the first positional argument to the wrapped method (i.e. self) is what __loader__ should be set to. Changed in version 3.4: Set __loader__ if set to None, as if the attribute does not exist. Deprecated since version 3.4: The import machinery takes care of this automatically.
@importlib.util.set_package
A decorator for importlib.abc.Loader.load_module() to set the __package__ attribute on the returned module. If __package__ is set and has a value other than None it will not be changed. Deprecated since version 3.4: The import machinery takes care of this automatically.
importlib.util.spec_from_loader(name, loader, *, origin=None, is_package=None)
A factory function for creating a ModuleSpec instance based on a loader. The parameters have the same meaning as they do for ModuleSpec. The function uses available loader APIs, such as InspectLoader.is_package(), to fill in any missing information on the spec. New in version 3.4.
importlib.util.spec_from_file_location(name, location, *, loader=None, submodule_search_locations=None)
A factory function for creating a ModuleSpec instance based on the path to a file. Missing information will be filled in on the spec by making use of loader APIs and by the implication that the module will be file-based. New in version 3.4. Changed in version 3.6: Accepts a path-like object.
importlib.util.source_hash(source_bytes)
Return the hash of source_bytes as bytes. A hash-based .pyc file embeds the source_hash() of the corresponding source file’s contents in its header. New in version 3.7.
class importlib.util.LazyLoader(loader)
A class which postpones the execution of the loader of a module until the module has an attribute accessed. This class only works with loaders that define exec_module() as control over what module type is used for the module is required. For those same reasons, the loader’s create_module() method must return None or a type for which its __class__ attribute can be mutated along with not using slots. Finally, modules which substitute the object placed into sys.modules will not work as there is no way to properly replace the module references throughout the interpreter safely; ValueError is raised if such a substitution is detected. Note For projects where startup time is critical, this class allows for potentially minimizing the cost of loading a module if it is never used. For projects where startup time is not essential then use of this class is heavily discouraged due to error messages created during loading being postponed and thus occurring out of context. New in version 3.5. Changed in version 3.6: Began calling create_module(), removing the compatibility warning for importlib.machinery.BuiltinImporter and importlib.machinery.ExtensionFileLoader.
classmethod factory(loader)
A static method which returns a callable that creates a lazy loader. This is meant to be used in situations where the loader is passed by class instead of by instance. suffixes = importlib.machinery.SOURCE_SUFFIXES
loader = importlib.machinery.SourceFileLoader
lazy_loader = importlib.util.LazyLoader.factory(loader)
finder = importlib.machinery.FileFinder(path, (lazy_loader, suffixes))
Examples Importing programmatically To programmatically import a module, use importlib.import_module(). import importlib
itertools = importlib.import_module('itertools')
Checking if a module can be imported If you need to find out if a module can be imported without actually doing the import, then you should use importlib.util.find_spec(). import importlib.util
import sys
# For illustrative purposes.
name = 'itertools'
if name in sys.modules:
print(f"{name!r} already in sys.modules")
elif (spec := importlib.util.find_spec(name)) is not None:
# If you chose to perform the actual import ...
module = importlib.util.module_from_spec(spec)
sys.modules[name] = module
spec.loader.exec_module(module)
print(f"{name!r} has been imported")
else:
print(f"can't find the {name!r} module")
Importing a source file directly To import a Python source file directly, use the following recipe (Python 3.5 and newer only): import importlib.util
import sys
# For illustrative purposes.
import tokenize
file_path = tokenize.__file__
module_name = tokenize.__name__
spec = importlib.util.spec_from_file_location(module_name, file_path)
module = importlib.util.module_from_spec(spec)
sys.modules[module_name] = module
spec.loader.exec_module(module)
Setting up an importer For deep customizations of import, you typically want to implement an importer. This means managing both the finder and loader side of things. For finders there are two flavours to choose from depending on your needs: a meta path finder or a path entry finder. The former is what you would put on sys.meta_path while the latter is what you create using a path entry hook on sys.path_hooks which works with sys.path entries to potentially create a finder. This example will show you how to register your own importers so that import will use them (for creating an importer for yourself, read the documentation for the appropriate classes defined within this package): import importlib.machinery
import sys
# For illustrative purposes only.
SpamMetaPathFinder = importlib.machinery.PathFinder
SpamPathEntryFinder = importlib.machinery.FileFinder
loader_details = (importlib.machinery.SourceFileLoader,
importlib.machinery.SOURCE_SUFFIXES)
# Setting up a meta path finder.
# Make sure to put the finder in the proper location in the list in terms of
# priority.
sys.meta_path.append(SpamMetaPathFinder)
# Setting up a path entry finder.
# Make sure to put the path hook in the proper location in the list in terms
# of priority.
sys.path_hooks.append(SpamPathEntryFinder.path_hook(loader_details))
Approximating importlib.import_module()
Import itself is implemented in Python code, making it possible to expose most of the import machinery through importlib. The following helps illustrate the various APIs that importlib exposes by providing an approximate implementation of importlib.import_module() (Python 3.4 and newer for the importlib usage, Python 3.6 and newer for other parts of the code). import importlib.util
import sys
def import_module(name, package=None):
"""An approximate implementation of import."""
absolute_name = importlib.util.resolve_name(name, package)
try:
return sys.modules[absolute_name]
except KeyError:
pass
path = None
if '.' in absolute_name:
parent_name, _, child_name = absolute_name.rpartition('.')
parent_module = import_module(parent_name)
path = parent_module.__spec__.submodule_search_locations
for finder in sys.meta_path:
spec = finder.find_spec(absolute_name, path)
if spec is not None:
break
else:
msg = f'No module named {absolute_name!r}'
raise ModuleNotFoundError(msg, name=absolute_name)
module = importlib.util.module_from_spec(spec)
sys.modules[absolute_name] = module
spec.loader.exec_module(module)
if path is not None:
setattr(parent_module, child_name, module)
return module | python.library.importlib |
class importlib.abc.ExecutionLoader
An abstract base class which inherits from InspectLoader that, when implemented, helps a module to be executed as a script. The ABC represents an optional PEP 302 protocol.
abstractmethod get_filename(fullname)
An abstract method that is to return the value of __file__ for the specified module. If no path is available, ImportError is raised. If source code is available, then the method should return the path to the source file, regardless of whether a bytecode was used to load the module. Changed in version 3.4: Raises ImportError instead of NotImplementedError. | python.library.importlib#importlib.abc.ExecutionLoader |
abstractmethod get_filename(fullname)
An abstract method that is to return the value of __file__ for the specified module. If no path is available, ImportError is raised. If source code is available, then the method should return the path to the source file, regardless of whether a bytecode was used to load the module. Changed in version 3.4: Raises ImportError instead of NotImplementedError. | python.library.importlib#importlib.abc.ExecutionLoader.get_filename |
class importlib.abc.FileLoader(fullname, path)
An abstract base class which inherits from ResourceLoader and ExecutionLoader, providing concrete implementations of ResourceLoader.get_data() and ExecutionLoader.get_filename(). The fullname argument is a fully resolved name of the module the loader is to handle. The path argument is the path to the file for the module. New in version 3.3.
name
The name of the module the loader can handle.
path
Path to the file of the module.
load_module(fullname)
Calls super’s load_module(). Deprecated since version 3.4: Use Loader.exec_module() instead.
abstractmethod get_filename(fullname)
Returns path.
abstractmethod get_data(path)
Reads path as a binary file and returns the bytes from it. | python.library.importlib#importlib.abc.FileLoader |
abstractmethod get_data(path)
Reads path as a binary file and returns the bytes from it. | python.library.importlib#importlib.abc.FileLoader.get_data |
abstractmethod get_filename(fullname)
Returns path. | python.library.importlib#importlib.abc.FileLoader.get_filename |
load_module(fullname)
Calls super’s load_module(). Deprecated since version 3.4: Use Loader.exec_module() instead. | python.library.importlib#importlib.abc.FileLoader.load_module |
name
The name of the module the loader can handle. | python.library.importlib#importlib.abc.FileLoader.name |
path
Path to the file of the module. | python.library.importlib#importlib.abc.FileLoader.path |
class importlib.abc.Finder
An abstract base class representing a finder. Deprecated since version 3.3: Use MetaPathFinder or PathEntryFinder instead.
abstractmethod find_module(fullname, path=None)
An abstract method for finding a loader for the specified module. Originally specified in PEP 302, this method was meant for use in sys.meta_path and in the path-based import subsystem. Changed in version 3.4: Returns None when called instead of raising NotImplementedError. | python.library.importlib#importlib.abc.Finder |
abstractmethod find_module(fullname, path=None)
An abstract method for finding a loader for the specified module. Originally specified in PEP 302, this method was meant for use in sys.meta_path and in the path-based import subsystem. Changed in version 3.4: Returns None when called instead of raising NotImplementedError. | python.library.importlib#importlib.abc.Finder.find_module |
class importlib.abc.InspectLoader
An abstract base class for a loader which implements the optional PEP 302 protocol for loaders that inspect modules.
get_code(fullname)
Return the code object for a module, or None if the module does not have a code object (as would be the case, for example, for a built-in module). Raise an ImportError if loader cannot find the requested module. Note While the method has a default implementation, it is suggested that it be overridden if possible for performance. Changed in version 3.4: No longer abstract and a concrete implementation is provided.
abstractmethod get_source(fullname)
An abstract method to return the source of a module. It is returned as a text string using universal newlines, translating all recognized line separators into '\n' characters. Returns None if no source is available (e.g. a built-in module). Raises ImportError if the loader cannot find the module specified. Changed in version 3.4: Raises ImportError instead of NotImplementedError.
is_package(fullname)
An abstract method to return a true value if the module is a package, a false value otherwise. ImportError is raised if the loader cannot find the module. Changed in version 3.4: Raises ImportError instead of NotImplementedError.
static source_to_code(data, path='<string>')
Create a code object from Python source. The data argument can be whatever the compile() function supports (i.e. string or bytes). The path argument should be the “path” to where the source code originated from, which can be an abstract concept (e.g. location in a zip file). With the subsequent code object one can execute it in a module by running exec(code, module.__dict__). New in version 3.4. Changed in version 3.5: Made the method static.
exec_module(module)
Implementation of Loader.exec_module(). New in version 3.4.
load_module(fullname)
Implementation of Loader.load_module(). Deprecated since version 3.4: use exec_module() instead. | python.library.importlib#importlib.abc.InspectLoader |
exec_module(module)
Implementation of Loader.exec_module(). New in version 3.4. | python.library.importlib#importlib.abc.InspectLoader.exec_module |
get_code(fullname)
Return the code object for a module, or None if the module does not have a code object (as would be the case, for example, for a built-in module). Raise an ImportError if loader cannot find the requested module. Note While the method has a default implementation, it is suggested that it be overridden if possible for performance. Changed in version 3.4: No longer abstract and a concrete implementation is provided. | python.library.importlib#importlib.abc.InspectLoader.get_code |
abstractmethod get_source(fullname)
An abstract method to return the source of a module. It is returned as a text string using universal newlines, translating all recognized line separators into '\n' characters. Returns None if no source is available (e.g. a built-in module). Raises ImportError if the loader cannot find the module specified. Changed in version 3.4: Raises ImportError instead of NotImplementedError. | python.library.importlib#importlib.abc.InspectLoader.get_source |
is_package(fullname)
An abstract method to return a true value if the module is a package, a false value otherwise. ImportError is raised if the loader cannot find the module. Changed in version 3.4: Raises ImportError instead of NotImplementedError. | python.library.importlib#importlib.abc.InspectLoader.is_package |
load_module(fullname)
Implementation of Loader.load_module(). Deprecated since version 3.4: use exec_module() instead. | python.library.importlib#importlib.abc.InspectLoader.load_module |
static source_to_code(data, path='<string>')
Create a code object from Python source. The data argument can be whatever the compile() function supports (i.e. string or bytes). The path argument should be the “path” to where the source code originated from, which can be an abstract concept (e.g. location in a zip file). With the subsequent code object one can execute it in a module by running exec(code, module.__dict__). New in version 3.4. Changed in version 3.5: Made the method static. | python.library.importlib#importlib.abc.InspectLoader.source_to_code |
class importlib.abc.Loader
An abstract base class for a loader. See PEP 302 for the exact definition for a loader. Loaders that wish to support resource reading should implement a get_resource_reader(fullname) method as specified by importlib.abc.ResourceReader. Changed in version 3.7: Introduced the optional get_resource_reader() method.
create_module(spec)
A method that returns the module object to use when importing a module. This method may return None, indicating that default module creation semantics should take place. New in version 3.4. Changed in version 3.5: Starting in Python 3.6, this method will not be optional when exec_module() is defined.
exec_module(module)
An abstract method that executes the module in its own namespace when a module is imported or reloaded. The module should already be initialized when exec_module() is called. When this method exists, create_module() must be defined. New in version 3.4. Changed in version 3.6: create_module() must also be defined.
load_module(fullname)
A legacy method for loading a module. If the module cannot be loaded, ImportError is raised, otherwise the loaded module is returned. If the requested module already exists in sys.modules, that module should be used and reloaded. Otherwise the loader should create a new module and insert it into sys.modules before any loading begins, to prevent recursion from the import. If the loader inserted a module and the load fails, it must be removed by the loader from sys.modules; modules already in sys.modules before the loader began execution should be left alone (see importlib.util.module_for_loader()). The loader should set several attributes on the module. (Note that some of these attributes can change when a module is reloaded):
__name__
The name of the module.
__file__
The path to where the module data is stored (not set for built-in modules).
__cached__
The path to where a compiled version of the module is/should be stored (not set when the attribute would be inappropriate).
__path__
A list of strings specifying the search path within a package. This attribute is not set on modules.
__package__
The fully-qualified name of the package under which the module was loaded as a submodule (or the empty string for top-level modules). For packages, it is the same as __name__. The importlib.util.module_for_loader() decorator can handle the details for __package__.
__loader__
The loader used to load the module. The importlib.util.module_for_loader() decorator can handle the details for __package__. When exec_module() is available then backwards-compatible functionality is provided. Changed in version 3.4: Raise ImportError when called instead of NotImplementedError. Functionality provided when exec_module() is available. Deprecated since version 3.4: The recommended API for loading a module is exec_module() (and create_module()). Loaders should implement it instead of load_module(). The import machinery takes care of all the other responsibilities of load_module() when exec_module() is implemented.
module_repr(module)
A legacy method which when implemented calculates and returns the given module’s repr, as a string. The module type’s default repr() will use the result of this method as appropriate. New in version 3.3. Changed in version 3.4: Made optional instead of an abstractmethod. Deprecated since version 3.4: The import machinery now takes care of this automatically. | python.library.importlib#importlib.abc.Loader |
create_module(spec)
A method that returns the module object to use when importing a module. This method may return None, indicating that default module creation semantics should take place. New in version 3.4. Changed in version 3.5: Starting in Python 3.6, this method will not be optional when exec_module() is defined. | python.library.importlib#importlib.abc.Loader.create_module |
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