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	""" codecs -- Python Codec Registry, API and helpers.


	Written by Marc-Andre Lemburg (mal@lemburg.com).

	(c) Copyright CNRI, All Rights Reserved. NO WARRANTY.

	"""

	import builtins
	import sys

	### Registry and builtin stateless codec functions

	try:
	from _codecs import *
	except ImportError as why:
	raise SystemError('Failed to load the builtin codecs: %s' % why)

	__all__ = ["register", "lookup", "open", "EncodedFile", "BOM", "BOM_BE",
	"BOM_LE", "BOM32_BE", "BOM32_LE", "BOM64_BE", "BOM64_LE",
	"BOM_UTF8", "BOM_UTF16", "BOM_UTF16_LE", "BOM_UTF16_BE",
	"BOM_UTF32", "BOM_UTF32_LE", "BOM_UTF32_BE",
	"CodecInfo", "Codec", "IncrementalEncoder", "IncrementalDecoder",
	"StreamReader", "StreamWriter",
	"StreamReaderWriter", "StreamRecoder",
	"getencoder", "getdecoder", "getincrementalencoder",
	"getincrementaldecoder", "getreader", "getwriter",
	"encode", "decode", "iterencode", "iterdecode",
	"strict_errors", "ignore_errors", "replace_errors",
	"xmlcharrefreplace_errors",
	"backslashreplace_errors", "namereplace_errors",
	"register_error", "lookup_error"]

	### Constants

	#
	# Byte Order Mark (BOM = ZERO WIDTH NO-BREAK SPACE = U+FEFF)
	# and its possible byte string values
	# for UTF8/UTF16/UTF32 output and little/big endian machines
	#

	# UTF-8
	BOM_UTF8 = b'\xef\xbb\xbf'

	# UTF-16, little endian
	BOM_LE = BOM_UTF16_LE = b'\xff\xfe'

	# UTF-16, big endian
	BOM_BE = BOM_UTF16_BE = b'\xfe\xff'

	# UTF-32, little endian
	BOM_UTF32_LE = b'\xff\xfe\x00\x00'

	# UTF-32, big endian
	BOM_UTF32_BE = b'\x00\x00\xfe\xff'

	if sys.byteorder == 'little':

	# UTF-16, native endianness
	BOM = BOM_UTF16 = BOM_UTF16_LE

	# UTF-32, native endianness
	BOM_UTF32 = BOM_UTF32_LE

	else:

	# UTF-16, native endianness
	BOM = BOM_UTF16 = BOM_UTF16_BE

	# UTF-32, native endianness
	BOM_UTF32 = BOM_UTF32_BE

	# Old broken names (don't use in new code)
	BOM32_LE = BOM_UTF16_LE
	BOM32_BE = BOM_UTF16_BE
	BOM64_LE = BOM_UTF32_LE
	BOM64_BE = BOM_UTF32_BE


	### Codec base classes (defining the API)

	class CodecInfo(tuple):
	"""Codec details when looking up the codec registry"""

	# Private API to allow Python 3.4 to denylist the known non-Unicode
	# codecs in the standard library. A more general mechanism to
	# reliably distinguish test encodings from other codecs will hopefully
	# be defined for Python 3.5
	#
	# See http://bugs.python.org/issue19619
	_is_text_encoding = True # Assume codecs are text encodings by default

	def __new__(cls, encode, decode, streamreader=None, streamwriter=None,
	incrementalencoder=None, incrementaldecoder=None, name=None,
	*, _is_text_encoding=None):
	self = tuple.__new__(cls, (encode, decode, streamreader, streamwriter))
	self.name = name
	self.encode = encode
	self.decode = decode
	self.incrementalencoder = incrementalencoder
	self.incrementaldecoder = incrementaldecoder
	self.streamwriter = streamwriter
	self.streamreader = streamreader
	if _is_text_encoding is not None:
	self._is_text_encoding = _is_text_encoding
	return self

	def __repr__(self):
	return "<%s.%s object for encoding %s at %#x>" % \
	(self.__class__.__module__, self.__class__.__qualname__,
	self.name, id(self))

	class Codec:

	""" Defines the interface for stateless encoders/decoders.

	The .encode()/.decode() methods may use different error
	handling schemes by providing the errors argument. These
	string values are predefined:

	'strict' - raise a ValueError error (or a subclass)
	'ignore' - ignore the character and continue with the next
	'replace' - replace with a suitable replacement character;
	Python will use the official U+FFFD REPLACEMENT
	CHARACTER for the builtin Unicode codecs on
	decoding and '?' on encoding.
	'surrogateescape' - replace with private code points U+DCnn.
	'xmlcharrefreplace' - Replace with the appropriate XML
	character reference (only for encoding).
	'backslashreplace' - Replace with backslashed escape sequences.
	'namereplace' - Replace with \\N{...} escape sequences
	(only for encoding).

	The set of allowed values can be extended via register_error.

	"""
	def encode(self, input, errors='strict'):

	""" Encodes the object input and returns a tuple (output
	object, length consumed).

	errors defines the error handling to apply. It defaults to
	'strict' handling.

	The method may not store state in the Codec instance. Use
	StreamWriter for codecs which have to keep state in order to
	make encoding efficient.

	The encoder must be able to handle zero length input and
	return an empty object of the output object type in this
	situation.

	"""
	raise NotImplementedError

	def decode(self, input, errors='strict'):

	""" Decodes the object input and returns a tuple (output
	object, length consumed).

	input must be an object which provides the bf_getreadbuf
	buffer slot. Python strings, buffer objects and memory
	mapped files are examples of objects providing this slot.

	errors defines the error handling to apply. It defaults to
	'strict' handling.

	The method may not store state in the Codec instance. Use
	StreamReader for codecs which have to keep state in order to
	make decoding efficient.

	The decoder must be able to handle zero length input and
	return an empty object of the output object type in this
	situation.

	"""
	raise NotImplementedError

	class IncrementalEncoder(object):
	"""
	An IncrementalEncoder encodes an input in multiple steps. The input can
	be passed piece by piece to the encode() method. The IncrementalEncoder
	remembers the state of the encoding process between calls to encode().
	"""
	def __init__(self, errors='strict'):
	"""
	Creates an IncrementalEncoder instance.

	The IncrementalEncoder may use different error handling schemes by
	providing the errors keyword argument. See the module docstring
	for a list of possible values.
	"""
	self.errors = errors
	self.buffer = ""

	def encode(self, input, final=False):
	"""
	Encodes input and returns the resulting object.
	"""
	raise NotImplementedError

	def reset(self):
	"""
	Resets the encoder to the initial state.
	"""

	def getstate(self):
	"""
	Return the current state of the encoder.
	"""
	return 0

	def setstate(self, state):
	"""
	Set the current state of the encoder. state must have been
	returned by getstate().
	"""

	class BufferedIncrementalEncoder(IncrementalEncoder):
	"""
	This subclass of IncrementalEncoder can be used as the baseclass for an
	incremental encoder if the encoder must keep some of the output in a
	buffer between calls to encode().
	"""
	def __init__(self, errors='strict'):
	IncrementalEncoder.__init__(self, errors)
	# unencoded input that is kept between calls to encode()
	self.buffer = ""

	def _buffer_encode(self, input, errors, final):
	# Overwrite this method in subclasses: It must encode input
	# and return an (output, length consumed) tuple
	raise NotImplementedError

	def encode(self, input, final=False):
	# encode input (taking the buffer into account)
	data = self.buffer + input
	(result, consumed) = self._buffer_encode(data, self.errors, final)
	# keep unencoded input until the next call
	self.buffer = data[consumed:]
	return result

	def reset(self):
	IncrementalEncoder.reset(self)
	self.buffer = ""

	def getstate(self):
	return self.buffer or 0

	def setstate(self, state):
	self.buffer = state or ""

	class IncrementalDecoder(object):
	"""
	An IncrementalDecoder decodes an input in multiple steps. The input can
	be passed piece by piece to the decode() method. The IncrementalDecoder
	remembers the state of the decoding process between calls to decode().
	"""
	def __init__(self, errors='strict'):
	"""
	Create an IncrementalDecoder instance.

	The IncrementalDecoder may use different error handling schemes by
	providing the errors keyword argument. See the module docstring
	for a list of possible values.
	"""
	self.errors = errors

	def decode(self, input, final=False):
	"""
	Decode input and returns the resulting object.
	"""
	raise NotImplementedError

	def reset(self):
	"""
	Reset the decoder to the initial state.
	"""

	def getstate(self):
	"""
	Return the current state of the decoder.

	This must be a (buffered_input, additional_state_info) tuple.
	buffered_input must be a bytes object containing bytes that
	were passed to decode() that have not yet been converted.
	additional_state_info must be a non-negative integer
	representing the state of the decoder WITHOUT yet having
	processed the contents of buffered_input. In the initial state
	and after reset(), getstate() must return (b"", 0).
	"""
	return (b"", 0)

	def setstate(self, state):
	"""
	Set the current state of the decoder.

	state must have been returned by getstate(). The effect of
	setstate((b"", 0)) must be equivalent to reset().
	"""

	class BufferedIncrementalDecoder(IncrementalDecoder):
	"""
	This subclass of IncrementalDecoder can be used as the baseclass for an
	incremental decoder if the decoder must be able to handle incomplete
	byte sequences.
	"""
	def __init__(self, errors='strict'):
	IncrementalDecoder.__init__(self, errors)
	# undecoded input that is kept between calls to decode()
	self.buffer = b""

	def _buffer_decode(self, input, errors, final):
	# Overwrite this method in subclasses: It must decode input
	# and return an (output, length consumed) tuple
	raise NotImplementedError

	def decode(self, input, final=False):
	# decode input (taking the buffer into account)
	data = self.buffer + input
	(result, consumed) = self._buffer_decode(data, self.errors, final)
	# keep undecoded input until the next call
	self.buffer = data[consumed:]
	return result

	def reset(self):
	IncrementalDecoder.reset(self)
	self.buffer = b""

	def getstate(self):
	# additional state info is always 0
	return (self.buffer, 0)

	def setstate(self, state):
	# ignore additional state info
	self.buffer = state[0]

	#
	# The StreamWriter and StreamReader class provide generic working
	# interfaces which can be used to implement new encoding submodules
	# very easily. See encodings/utf_8.py for an example on how this is
	# done.
	#

	class StreamWriter(Codec):

	def __init__(self, stream, errors='strict'):

	""" Creates a StreamWriter instance.

	stream must be a file-like object open for writing.

	The StreamWriter may use different error handling
	schemes by providing the errors keyword argument. These
	parameters are predefined:

	'strict' - raise a ValueError (or a subclass)
	'ignore' - ignore the character and continue with the next
	'replace'- replace with a suitable replacement character
	'xmlcharrefreplace' - Replace with the appropriate XML
	character reference.
	'backslashreplace' - Replace with backslashed escape
	sequences.
	'namereplace' - Replace with \\N{...} escape sequences.

	The set of allowed parameter values can be extended via
	register_error.
	"""
	self.stream = stream
	self.errors = errors

	def write(self, object):

	""" Writes the object's contents encoded to self.stream.
	"""
	data, consumed = self.encode(object, self.errors)
	self.stream.write(data)

	def writelines(self, list):

	""" Writes the concatenated list of strings to the stream
	using .write().
	"""
	self.write(''.join(list))

	def reset(self):

	""" Resets the codec buffers used for keeping internal state.

	Calling this method should ensure that the data on the
	output is put into a clean state, that allows appending
	of new fresh data without having to rescan the whole
	stream to recover state.

	"""
	pass

	def seek(self, offset, whence=0):
	self.stream.seek(offset, whence)
	if whence == 0 and offset == 0:
	self.reset()

	def __getattr__(self, name,
	getattr=getattr):

	""" Inherit all other methods from the underlying stream.
	"""
	return getattr(self.stream, name)

	def __enter__(self):
	return self

	def __exit__(self, type, value, tb):
	self.stream.close()

	###

	class StreamReader(Codec):

	charbuffertype = str

	def __init__(self, stream, errors='strict'):

	""" Creates a StreamReader instance.

	stream must be a file-like object open for reading.

	The StreamReader may use different error handling
	schemes by providing the errors keyword argument. These
	parameters are predefined:

	'strict' - raise a ValueError (or a subclass)
	'ignore' - ignore the character and continue with the next
	'replace'- replace with a suitable replacement character
	'backslashreplace' - Replace with backslashed escape sequences;

	The set of allowed parameter values can be extended via
	register_error.
	"""
	self.stream = stream
	self.errors = errors
	self.bytebuffer = b""
	self._empty_charbuffer = self.charbuffertype()
	self.charbuffer = self._empty_charbuffer
	self.linebuffer = None

	def decode(self, input, errors='strict'):
	raise NotImplementedError

	def read(self, size=-1, chars=-1, firstline=False):

	""" Decodes data from the stream self.stream and returns the
	resulting object.

	chars indicates the number of decoded code points or bytes to
	return. read() will never return more data than requested,
	but it might return less, if there is not enough available.

	size indicates the approximate maximum number of decoded
	bytes or code points to read for decoding. The decoder
	can modify this setting as appropriate. The default value
	-1 indicates to read and decode as much as possible. size
	is intended to prevent having to decode huge files in one
	step.

	If firstline is true, and a UnicodeDecodeError happens
	after the first line terminator in the input only the first line
	will be returned, the rest of the input will be kept until the
	next call to read().

	The method should use a greedy read strategy, meaning that
	it should read as much data as is allowed within the
	definition of the encoding and the given size, e.g. if
	optional encoding endings or state markers are available
	on the stream, these should be read too.
	"""
	# If we have lines cached, first merge them back into characters
	if self.linebuffer:
	self.charbuffer = self._empty_charbuffer.join(self.linebuffer)
	self.linebuffer = None

	if chars < 0:
	# For compatibility with other read() methods that take a
	# single argument
	chars = size

	# read until we get the required number of characters (if available)
	while True:
	# can the request be satisfied from the character buffer?
	if chars >= 0:
	if len(self.charbuffer) >= chars:
	break
	# we need more data
	if size < 0:
	newdata = self.stream.read()
	else:
	newdata = self.stream.read(size)
	# decode bytes (those remaining from the last call included)
	data = self.bytebuffer + newdata
	if not data:
	break
	try:
	newchars, decodedbytes = self.decode(data, self.errors)
	except UnicodeDecodeError as exc:
	if firstline:
	newchars, decodedbytes = \
	self.decode(data[:exc.start], self.errors)
	lines = newchars.splitlines(keepends=True)
	if len(lines)<=1:
	raise
	else:
	raise
	# keep undecoded bytes until the next call
	self.bytebuffer = data[decodedbytes:]
	# put new characters in the character buffer
	self.charbuffer += newchars
	# there was no data available
	if not newdata:
	break
	if chars < 0:
	# Return everything we've got
	result = self.charbuffer
	self.charbuffer = self._empty_charbuffer
	else:
	# Return the first chars characters
	result = self.charbuffer[:chars]
	self.charbuffer = self.charbuffer[chars:]
	return result

	def readline(self, size=None, keepends=True):

	""" Read one line from the input stream and return the
	decoded data.

	size, if given, is passed as size argument to the
	read() method.

	"""
	# If we have lines cached from an earlier read, return
	# them unconditionally
	if self.linebuffer:
	line = self.linebuffer[0]
	del self.linebuffer[0]
	if len(self.linebuffer) == 1:
	# revert to charbuffer mode; we might need more data
	# next time
	self.charbuffer = self.linebuffer[0]
	self.linebuffer = None
	if not keepends:
	line = line.splitlines(keepends=False)[0]
	return line

	readsize = size or 72
	line = self._empty_charbuffer
	# If size is given, we call read() only once
	while True:
	data = self.read(readsize, firstline=True)
	if data:
	# If we're at a "\r" read one extra character (which might
	# be a "\n") to get a proper line ending. If the stream is
	# temporarily exhausted we return the wrong line ending.
	if (isinstance(data, str) and data.endswith("\r")) or \
	(isinstance(data, bytes) and data.endswith(b"\r")):
	data += self.read(size=1, chars=1)

	line += data
	lines = line.splitlines(keepends=True)
	if lines:
	if len(lines) > 1:
	# More than one line result; the first line is a full line
	# to return
	line = lines[0]
	del lines[0]
	if len(lines) > 1:
	# cache the remaining lines
	lines[-1] += self.charbuffer
	self.linebuffer = lines
	self.charbuffer = None
	else:
	# only one remaining line, put it back into charbuffer
	self.charbuffer = lines[0] + self.charbuffer
	if not keepends:
	line = line.splitlines(keepends=False)[0]
	break
	line0withend = lines[0]
	line0withoutend = lines[0].splitlines(keepends=False)[0]
	if line0withend != line0withoutend: # We really have a line end
	# Put the rest back together and keep it until the next call
	self.charbuffer = self._empty_charbuffer.join(lines[1:]) + \
	self.charbuffer
	if keepends:
	line = line0withend
	else:
	line = line0withoutend
	break
	# we didn't get anything or this was our only try
	if not data or size is not None:
	if line and not keepends:
	line = line.splitlines(keepends=False)[0]
	break
	if readsize < 8000:
	readsize *= 2
	return line

	def readlines(self, sizehint=None, keepends=True):

	""" Read all lines available on the input stream
	and return them as a list.

	Line breaks are implemented using the codec's decoder
	method and are included in the list entries.

	sizehint, if given, is ignored since there is no efficient
	way to finding the true end-of-line.

	"""
	data = self.read()
	return data.splitlines(keepends)

	def reset(self):

	""" Resets the codec buffers used for keeping internal state.

	Note that no stream repositioning should take place.
	This method is primarily intended to be able to recover
	from decoding errors.

	"""
	self.bytebuffer = b""
	self.charbuffer = self._empty_charbuffer
	self.linebuffer = None

	def seek(self, offset, whence=0):
	""" Set the input stream's current position.

	Resets the codec buffers used for keeping state.
	"""
	self.stream.seek(offset, whence)
	self.reset()

	def __next__(self):

	""" Return the next decoded line from the input stream."""
	line = self.readline()
	if line:
	return line
	raise StopIteration

	def __iter__(self):
	return self

	def __getattr__(self, name,
	getattr=getattr):

	""" Inherit all other methods from the underlying stream.
	"""
	return getattr(self.stream, name)

	def __enter__(self):
	return self

	def __exit__(self, type, value, tb):
	self.stream.close()

	###

	class StreamReaderWriter:

	""" StreamReaderWriter instances allow wrapping streams which
	work in both read and write modes.

	The design is such that one can use the factory functions
	returned by the codec.lookup() function to construct the
	instance.

	"""
	# Optional attributes set by the file wrappers below
	encoding = 'unknown'

	def __init__(self, stream, Reader, Writer, errors='strict'):

	""" Creates a StreamReaderWriter instance.

	stream must be a Stream-like object.

	Reader, Writer must be factory functions or classes
	providing the StreamReader, StreamWriter interface resp.

	Error handling is done in the same way as defined for the
	StreamWriter/Readers.

	"""
	self.stream = stream
	self.reader = Reader(stream, errors)
	self.writer = Writer(stream, errors)
	self.errors = errors

	def read(self, size=-1):

	return self.reader.read(size)

	def readline(self, size=None):

	return self.reader.readline(size)

	def readlines(self, sizehint=None):

	return self.reader.readlines(sizehint)

	def __next__(self):

	""" Return the next decoded line from the input stream."""
	return next(self.reader)

	def __iter__(self):
	return self

	def write(self, data):

	return self.writer.write(data)

	def writelines(self, list):

	return self.writer.writelines(list)

	def reset(self):

	self.reader.reset()
	self.writer.reset()

	def seek(self, offset, whence=0):
	self.stream.seek(offset, whence)
	self.reader.reset()
	if whence == 0 and offset == 0:
	self.writer.reset()

	def __getattr__(self, name,
	getattr=getattr):

	""" Inherit all other methods from the underlying stream.
	"""
	return getattr(self.stream, name)

	# these are needed to make "with StreamReaderWriter(...)" work properly

	def __enter__(self):
	return self

	def __exit__(self, type, value, tb):
	self.stream.close()

	###

	class StreamRecoder:

	""" StreamRecoder instances translate data from one encoding to another.

	They use the complete set of APIs returned by the
	codecs.lookup() function to implement their task.

	Data written to the StreamRecoder is first decoded into an
	intermediate format (depending on the "decode" codec) and then
	written to the underlying stream using an instance of the provided
	Writer class.

	In the other direction, data is read from the underlying stream using
	a Reader instance and then encoded and returned to the caller.

	"""
	# Optional attributes set by the file wrappers below
	data_encoding = 'unknown'
	file_encoding = 'unknown'

	def __init__(self, stream, encode, decode, Reader, Writer,
	errors='strict'):

	""" Creates a StreamRecoder instance which implements a two-way
	conversion: encode and decode work on the frontend (the
	data visible to .read() and .write()) while Reader and Writer
	work on the backend (the data in stream).

	You can use these objects to do transparent
	transcodings from e.g. latin-1 to utf-8 and back.

	stream must be a file-like object.

	encode and decode must adhere to the Codec interface; Reader and
	Writer must be factory functions or classes providing the
	StreamReader and StreamWriter interfaces resp.

	Error handling is done in the same way as defined for the
	StreamWriter/Readers.

	"""
	self.stream = stream
	self.encode = encode
	self.decode = decode
	self.reader = Reader(stream, errors)
	self.writer = Writer(stream, errors)
	self.errors = errors

	def read(self, size=-1):

	data = self.reader.read(size)
	data, bytesencoded = self.encode(data, self.errors)
	return data

	def readline(self, size=None):

	if size is None:
	data = self.reader.readline()
	else:
	data = self.reader.readline(size)
	data, bytesencoded = self.encode(data, self.errors)
	return data

	def readlines(self, sizehint=None):

	data = self.reader.read()
	data, bytesencoded = self.encode(data, self.errors)
	return data.splitlines(keepends=True)

	def __next__(self):

	""" Return the next decoded line from the input stream."""
	data = next(self.reader)
	data, bytesencoded = self.encode(data, self.errors)
	return data

	def __iter__(self):
	return self

	def write(self, data):

	data, bytesdecoded = self.decode(data, self.errors)
	return self.writer.write(data)

	def writelines(self, list):

	data = b''.join(list)
	data, bytesdecoded = self.decode(data, self.errors)
	return self.writer.write(data)

	def reset(self):

	self.reader.reset()
	self.writer.reset()

	def seek(self, offset, whence=0):
	# Seeks must be propagated to both the readers and writers
	# as they might need to reset their internal buffers.
	self.reader.seek(offset, whence)
	self.writer.seek(offset, whence)

	def __getattr__(self, name,
	getattr=getattr):

	""" Inherit all other methods from the underlying stream.
	"""
	return getattr(self.stream, name)

	def __enter__(self):
	return self

	def __exit__(self, type, value, tb):
	self.stream.close()

	### Shortcuts

	def open(filename, mode='r', encoding=None, errors='strict', buffering=-1):

	""" Open an encoded file using the given mode and return
	a wrapped version providing transparent encoding/decoding.

	Note: The wrapped version will only accept the object format
	defined by the codecs, i.e. Unicode objects for most builtin
	codecs. Output is also codec dependent and will usually be
	Unicode as well.

	If encoding is not None, then the
	underlying encoded files are always opened in binary mode.
	The default file mode is 'r', meaning to open the file in read mode.

	encoding specifies the encoding which is to be used for the
	file.

	errors may be given to define the error handling. It defaults
	to 'strict' which causes ValueErrors to be raised in case an
	encoding error occurs.

	buffering has the same meaning as for the builtin open() API.
	It defaults to -1 which means that the default buffer size will
	be used.

	The returned wrapped file object provides an extra attribute
	.encoding which allows querying the used encoding. This
	attribute is only available if an encoding was specified as
	parameter.

	"""
	if encoding is not None and \
	'b' not in mode:
	# Force opening of the file in binary mode
	mode = mode + 'b'
	file = builtins.open(filename, mode, buffering)
	if encoding is None:
	return file

	try:
	info = lookup(encoding)
	srw = StreamReaderWriter(file, info.streamreader, info.streamwriter, errors)
	# Add attributes to simplify introspection
	srw.encoding = encoding
	return srw
	except:
	file.close()
	raise

	def EncodedFile(file, data_encoding, file_encoding=None, errors='strict'):

	""" Return a wrapped version of file which provides transparent
	encoding translation.

	Data written to the wrapped file is decoded according
	to the given data_encoding and then encoded to the underlying
	file using file_encoding. The intermediate data type
	will usually be Unicode but depends on the specified codecs.

	Bytes read from the file are decoded using file_encoding and then
	passed back to the caller encoded using data_encoding.

	If file_encoding is not given, it defaults to data_encoding.

	errors may be given to define the error handling. It defaults
	to 'strict' which causes ValueErrors to be raised in case an
	encoding error occurs.

	The returned wrapped file object provides two extra attributes
	.data_encoding and .file_encoding which reflect the given
	parameters of the same name. The attributes can be used for
	introspection by Python programs.

	"""
	if file_encoding is None:
	file_encoding = data_encoding
	data_info = lookup(data_encoding)
	file_info = lookup(file_encoding)
	sr = StreamRecoder(file, data_info.encode, data_info.decode,
	file_info.streamreader, file_info.streamwriter, errors)
	# Add attributes to simplify introspection
	sr.data_encoding = data_encoding
	sr.file_encoding = file_encoding
	return sr

	### Helpers for codec lookup

	def getencoder(encoding):

	""" Lookup up the codec for the given encoding and return
	its encoder function.

	Raises a LookupError in case the encoding cannot be found.

	"""
	return lookup(encoding).encode

	def getdecoder(encoding):

	""" Lookup up the codec for the given encoding and return
	its decoder function.

	Raises a LookupError in case the encoding cannot be found.

	"""
	return lookup(encoding).decode

	def getincrementalencoder(encoding):

	""" Lookup up the codec for the given encoding and return
	its IncrementalEncoder class or factory function.

	Raises a LookupError in case the encoding cannot be found
	or the codecs doesn't provide an incremental encoder.

	"""
	encoder = lookup(encoding).incrementalencoder
	if encoder is None:
	raise LookupError(encoding)
	return encoder

	def getincrementaldecoder(encoding):

	""" Lookup up the codec for the given encoding and return
	its IncrementalDecoder class or factory function.

	Raises a LookupError in case the encoding cannot be found
	or the codecs doesn't provide an incremental decoder.

	"""
	decoder = lookup(encoding).incrementaldecoder
	if decoder is None:
	raise LookupError(encoding)
	return decoder

	def getreader(encoding):

	""" Lookup up the codec for the given encoding and return
	its StreamReader class or factory function.

	Raises a LookupError in case the encoding cannot be found.

	"""
	return lookup(encoding).streamreader

	def getwriter(encoding):

	""" Lookup up the codec for the given encoding and return
	its StreamWriter class or factory function.

	Raises a LookupError in case the encoding cannot be found.

	"""
	return lookup(encoding).streamwriter

	def iterencode(iterator, encoding, errors='strict', **kwargs):
	"""
	Encoding iterator.

	Encodes the input strings from the iterator using an IncrementalEncoder.

	errors and kwargs are passed through to the IncrementalEncoder
	constructor.
	"""
	encoder = getincrementalencoder(encoding)(errors, **kwargs)
	for input in iterator:
	output = encoder.encode(input)
	if output:
	yield output
	output = encoder.encode("", True)
	if output:
	yield output

	def iterdecode(iterator, encoding, errors='strict', **kwargs):
	"""
	Decoding iterator.

	Decodes the input strings from the iterator using an IncrementalDecoder.

	errors and kwargs are passed through to the IncrementalDecoder
	constructor.
	"""
	decoder = getincrementaldecoder(encoding)(errors, **kwargs)
	for input in iterator:
	output = decoder.decode(input)
	if output:
	yield output
	output = decoder.decode(b"", True)
	if output:
	yield output

	### Helpers for charmap-based codecs

	def make_identity_dict(rng):

	""" make_identity_dict(rng) -> dict

	Return a dictionary where elements of the rng sequence are
	mapped to themselves.

	"""
	return {i:i for i in rng}

	def make_encoding_map(decoding_map):

	""" Creates an encoding map from a decoding map.

	If a target mapping in the decoding map occurs multiple
	times, then that target is mapped to None (undefined mapping),
	causing an exception when encountered by the charmap codec
	during translation.

	One example where this happens is cp875.py which decodes
	multiple character to \\u001a.

	"""
	m = {}
	for k,v in decoding_map.items():
	if not v in m:
	m[v] = k
	else:
	m[v] = None
	return m

	### error handlers

	try:
	strict_errors = lookup_error("strict")
	ignore_errors = lookup_error("ignore")
	replace_errors = lookup_error("replace")
	xmlcharrefreplace_errors = lookup_error("xmlcharrefreplace")
	backslashreplace_errors = lookup_error("backslashreplace")
	namereplace_errors = lookup_error("namereplace")
	except LookupError:
	# In --disable-unicode builds, these error handler are missing
	strict_errors = None
	ignore_errors = None
	replace_errors = None
	xmlcharrefreplace_errors = None
	backslashreplace_errors = None
	namereplace_errors = None

	# Tell modulefinder that using codecs probably needs the encodings
	# package
	_false = 0
	if _false:
	import encodings

	### Tests

	if __name__ == '__main__':

	# Make stdout translate Latin-1 output into UTF-8 output
	sys.stdout = EncodedFile(sys.stdout, 'latin-1', 'utf-8')

	# Have stdin translate Latin-1 input into UTF-8 input
	sys.stdin = EncodedFile(sys.stdin, 'utf-8', 'latin-1')