Update app.py

Another 'None' bug fix attempt

app.py

@@ -21,13 +21,14 @@ def my_custom_tool(arg1:str, arg2:int)-> str: #it's import to specify the return
 @tool
 def get_web_search_results(query: str)-> str: #it's import to specify the return type
     #Keep this format for the description / args / args description but feel free to modify the tool
-    """A tool that searchs the web using a query
+    """A tool that searchs the web using a query.
     Args:
-        query: A string representing a valid web query (e.g. 'pictures of cats')
+        query: A string representing a valid web query. IMPORTANT: Follow type str format strictly e.g. 'pictures of cats'.
+        Incorrect formatting (such as, query='picture of cats') will result in None being returned. 
     """
     try:
         results = DuckDuckGoSearchTool.forward(query)
-        if results:
+        if results and results != "None":
             return results
         else:
             return "Your query may be incorrectly formatted. Ensure it is of type str e.g. 'bananas'"