code: def testUseWithoutStrategy(self):
      # There's no perfect way to check if the test runs in a subprocess. We
      # approximate by checking the presence of TF_CONFIG, which is normally not
      # set to the main process.
      self.assertNotEqual(os.getenv("TF_CONFIG"), "")
  
imports: import importlib
  import os
  import sys
  import unittest
  from absl.testing import parameterized
  from tensorflow.python.distribute import combinations
  from tensorflow.python.distribute import test_util
  from tensorflow.python.distribute.cluster_resolver import tfconfig_cluster_resolver
  from tensorflow.python.eager import context
  from tensorflow.python.framework import combinations
  from tensorflow.python.platform import test
label_desc: Use image node_id 6 for calling the ClusterCombinationTest obj's underlying member method code with example usage: obj.testUseWithoutStrategy() without return types