code: def rpc_register(call: RPCCallBase) -> int:
      r"""Registers a call for RPC requests."""
      global _rpc_call_id, _rpc_call_pool
  
      with _rpc_call_lock:
          call_id = _rpc_call_id
          _rpc_call_id += 1
          if call_id in _rpc_call_pool:
              raise RuntimeError(
                  "Registered function twice in 'rpc_register'"
              )
          _rpc_call_pool[call_id] = call
  
      return call_id
  
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 8 for calling a global function with example usage: rpc_register(call) and returns: call_id