code: def test_environment_variable_context() -> None:
      name = "ENV_VAR_TEST"
      assert name not in os.environ
      with utils.environment_variables(ENV_VAR_TEST="blublu"):
          assert os.environ[name] == "blublu"
          with utils.environment_variables(ENV_VAR_TEST="blublu2"):
              assert os.environ[name] == "blublu2"
          assert os.environ[name] == "blublu"
      assert name not in os.environ
  
file_path: submitit/submitit/core/test_utils.py
imports: import os
  import shutil
  import sys
  from pathlib import Path
  from typing import Optional
  import pytest
  from .None import utils
label_desc: Use image node_id 5 for calling a global function with example usage: test_environment_variable_context() without return types