code: def get_draining_node_ids(self) -> Set[str]:
      return set()
  
file_path: ray/python/ray/serve/_private/cluster_node_info_cache.py
imports: from abc import ABC, abstractmethod
  from typing import List, Optional, Set, Tuple
  import ray
  from ray._raylet import GcsClient
  from ray.serve._private.constants import RAY_GCS_RPC_TIMEOUT_S
label_desc: Use image node_id 2 for calling the DefaultClusterNodeInfoCache obj's underlying member method code with example usage: obj.get_draining_node_ids() and returns: set