docs: def GetNotificationsForAllShards(self, queue):
      """Returns notifications for all shards of a queue at once.
  
      Used by worker_test_lib.MockWorker to cover all shards with a single worker.
  
      Args:
        queue: usually rdfvalue.RDFURN("aff4:/W")
  
      Returns:
        List of rdf_flows.GrrNotification objects
      """
      notifications_by_session_id = {}
      for queue_shard in self.GetAllNotificationShards(queue):
        self._GetUnsortedNotifications(
            queue_shard, notifications_by_session_id=notifications_by_session_id)
  
      return notifications_by_session_id.values()