code: def init_process_group() -> None:
      if "OMPI_COMM_WORLD_SIZE" not in os.environ:
          pytest.skip("This test is expected to be launch with mpirun.")
  
      # This function is automatically called at the beginning of the pytest session.
      os.environ["WORLD_SIZE"] = os.environ["OMPI_COMM_WORLD_SIZE"]
      os.environ["RANK"] = os.environ["OMPI_COMM_WORLD_RANK"]
      os.environ["MASTER_ADDR"] = "127.0.0.1"
      os.environ["MASTER_PORT"] = "20000"
  
      dist.init_process_group(
          "gloo", timeout=datetime.timedelta(seconds=15)
      )
  
imports: import datetime
  import os
  from typing import Optional
  import pytest
  import optuna
  from optuna._imports import try_import
  from optuna.integration import TorchDistributedTrial
  from optuna.testing.pruners import DeterministicPruner
  from optuna.testing.storages import StorageSupplier
label_desc: Use image node_id 1 for calling a global function with example usage: init_process_group() without return types