def dispatch_non_api_requests(self, request, start_response):
    """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.
    """
    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