code: def test_global_pool(self):
      _global_pool.run(fn_that_does_nothing)
  
imports: import ctypes
  import json
  import os
  import sys
  import threading
  import time
  import unittest
  from absl import logging
  from absl.testing import parameterized
  from tensorflow.python.distribute import combinations
  from tensorflow.python.distribute import multi_process_runner
  from tensorflow.python.distribute import multi_worker_test_base
  from tensorflow.python.eager import context
  from tensorflow.python.eager import test
label_desc: Use image node_id 6 for calling the MultiProcessPoolRunnerTest obj's underlying member method code with example usage: obj.test_global_pool() without return types