code: def receive(self):
          
          pickled_request = self._connection.connection.lpop(self._request_key)
          return pickle.loads(pickled_request) if pickled_request is not None else None
docs: Returns a single request.
  
          Takes the first request from the list of requests and returns it. If the list
          is empty, None is returned.
  
          Returns:
              Response: If a new request is available a Request object is returned,
                        otherwise None is returned.