code: def shutdown_rpc(
      id: str = None, graceful: bool = True, timeout: float = 240.0
  ):
      with _rpc_init_lock:
          if rpc_is_initialized():
              global_barrier(timeout=timeout)
              rpc.shutdown(graceful, timeout)
              logging.debug(f"Closed RPC in {id} (graceful={graceful})")
          else:
              logging.error(f"RPC in {id} not initialized.")
  
imports: import logging
  import threading
  from abc import ABC, abstractmethod
  from typing import Any, Callable, Dict, List, Optional
  from torch.distributed import rpc
  from torch_geometric.distributed.dist_context import DistContext, DistRole
label_desc: Use image node_id 6 for calling a global function with example usage: shutdown_rpc(id, graceful, timeout) without return types