code: def _poll_request(self):
      return gcs_service_pb2.GcsSubscriberPollRequest(
          subscriber_id=self._subscriber_id,
          max_processed_sequence_id=self._max_processed_sequence_id,
          publisher_id=self._publisher_id,
      )
  
imports: import asyncio
  from collections import deque
  import logging
  import random
  from typing import Tuple, List
  import grpc
  from ray._private.utils import get_or_create_event_loop
  import ray._private.gcs_utils
  import ray._private.logging_utils
  from ray.core.generated.gcs_pb2 import ErrorTableData
  from ray.core.generated import dependency_pb2
  from ray.core.generated import gcs_service_pb2_grpc
  from ray.core.generated import gcs_service_pb2
  from ray.core.generated import common_pb2
  from ray.core.generated import pubsub_pb2
label_desc: Use image node_id 4 for calling the _SubscriberBase obj's underlying member method code with example usage: obj._poll_request() and returns: gcs_service_pb2