code: def test_custom_context_used_python3_posix():
      """The 'multiprocessing.context' config is used to create the pool.
  
      We assume default is 'spawn', and therefore test for 'fork'.
      """
      # We check for 'fork' by ensuring subprocess doesn't have modules only
      # parent process should have:
  
      def check_for_pytest():
          import sys
  
          return "FAKE_MODULE_FOR_TEST" in sys.modules
  
      import sys
  
      sys.modules["FAKE_MODULE_FOR_TEST"] = 1
      try:
          with dask.config.set({"multiprocessing.context": "fork"}):
              result = get({"x": (check_for_pytest,)}, "x")
          assert result
      finally:
          del sys.modules["FAKE_MODULE_FOR_TEST"]
  
imports: from __future__ import annotations
  import multiprocessing
  import pickle
  import sys
  from concurrent.futures import ProcessPoolExecutor
  from operator import add
  import pytest
  import dask
  from dask import compute, delayed
  from dask.multiprocessing import _dumps, _loads, get, get_context, remote_exception
  from dask.system import CPU_COUNT
  from dask.utils_test import inc
label_desc: Use image node_id 22 for calling a global function with example usage: test_custom_context_used_python3_posix() and returns: unknown