code: def _send_group_coordinator_request(self):
          
          node_id = self._client.least_loaded_node()
          if node_id is None:
              return Future().failure(Errors.NoBrokersAvailable())
  
          elif not self._client.ready(node_id, metadata_priority=False):
              e = Errors.NodeNotReadyError(node_id)
              return Future().failure(e)
  
          log.debug("Sending group coordinator request for group %s to broker %s",
                    self.group_id, node_id)
          request = GroupCoordinatorRequest[0](self.group_id)
          future = Future()
          _f = self._client.send(node_id, request)
          _f.add_callback(self._handle_group_coordinator_response, future)
          _f.add_errback(self._failed_request, node_id, request, future)
          return future
docs: Discover the current coordinator for the group.
  
          Returns:
              Future: resolves to the node id of the coordinator