code: def _wait_all_workers(timeout=DEFAULT_SHUTDOWN_TIMEOUT):
      r"""
      Block until all local and remote RPC processes reach this method and wait
      for all outstanding work to complete. Every RPC process must call this
      method before exit to perform a graceful shutdown. This should be used to
      terminate the RPC framework, and there is no guarantee that the RPC
      framework will work after this method returns.
      """
      try:
          _all_gather(None, timeout=timeout)
      except RuntimeError as ex:
          logger.error(
              "Failed to respond to 'Shutdown Proceed' in time, got error %s",
              ex,
          )
          raise ex
  
imports: import collections
  import contextlib
  import functools
  import inspect
  import logging
  import threading
  from typing import Dict, Generic, TypeVar, Set, Any, TYPE_CHECKING
  import torch
  from torch.futures import Future
  from torch._C._distributed_rpc import PyRRef, RemoteProfilerManager, WorkerInfo, TensorPipeAgent, get_rpc_timeout, _cleanup_python_rpc_handler, _delete_all_user_and_unforked_owner_rrefs, _destroy_rref_context, _get_current_rpc_agent, _invoke_remote_builtin, _invoke_remote_python_udf, _invoke_remote_torchscript, _invoke_rpc_builtin, _invoke_rpc_python_udf, _invoke_rpc_torchscript, _is_current_rpc_agent_set, _reset_current_rpc_agent, _set_and_start_rpc_agent
  from .internal import PythonUDF, RPCExecMode, _internal_rpc_pickler, _build_rpc_profiling_key
  from .constants import DEFAULT_SHUTDOWN_TIMEOUT, UNSET_RPC_TIMEOUT
  from ._utils import _group_membership_management, _update_group_membership
label_desc: Use image node_id 9 for calling a global function with example usage: _wait_all_workers(timeout) without return types