code: def test_clean_env() -> None:
      base = _get_env()
      with utils.environment_variables(
          SLURM_BLUBLU=12, SUBMITIT_BLUBLU=12
      ):
          assert len(_get_env()) == len(base) + 2
          with helpers.clean_env():
              assert not _get_env()
          assert len(_get_env()) == len(base) + 2
      assert _get_env() == base
  
imports: import os
  import time
  import typing
  from pathlib import Path
  import pytest
  from .None import helpers
  from .core import core, utils
label_desc: Use image node_id 10 for calling a global function with example usage: test_clean_env() without return types