code: def dispatch_non_api_requests(self, request, start_response):
      
      for path_regex, dispatch_function in self._dispatchers:
        if path_regex.match(request.relative_url):
          return dispatch_function(request, start_response)
  
      if request.http_method == 'OPTIONS':
        cors_handler = self._create_cors_handler(request)
        if cors_handler.allow_cors_request:
          # The server returns 200 rather than 204, for some reason.
          return util.send_wsgi_response('200', [], '', start_response,
                                         cors_handler)
  
      return None
docs: Dispatch this request if this is a request to a reserved URL.
  
      If the request matches one of our reserved URLs, this calls
      start_response and returns the response body.  This also handles OPTIONS
      CORS requests.
  
      Args:
        request: An ApiRequest, the request from the user.
        start_response: A function with semantics defined in PEP-333.
  
      Returns:
        None if the request doesn't match one of the reserved URLs this
        handles.  Otherwise, returns the response body.