code: def register_listener(self, listener):
      self._listeners.add(listener)
  
imports: import os
  import threading
  from enum import IntFlag
  from horovod.runner.common.util import network, secret
  from horovod.runner.elastic.rendezvous import PUT_WORKER_ADDRESSES
  from horovod.runner.http.http_client import put_data_into_kvstore
label_desc: Use image node_id 3 for calling the WorkerNotificationManager obj's underlying member method code with example usage: obj.register_listener(listener) without return types