code: def test_stdout_captured(self):
      def simple_print_func():
          print("This is something printed.", flush=True)
          return "This is returned data."
  
      mpr_result = multi_process_runner.run(
          simple_print_func,
          multi_worker_test_base.create_cluster_spec(num_workers=2),
          return_output=True,
      )
      std_stream_results = mpr_result.stdout
      return_value = mpr_result.return_value
      self.assertIn(
          "[worker-0]:    This is something printed.\n",
          std_stream_results,
      )
      self.assertIn(
          "[worker-1]:    This is something printed.\n",
          std_stream_results,
      )
      self.assertIn("This is returned data.", return_value)
  
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 MultiProcessRunnerTest obj's underlying member method code with example usage: obj.test_stdout_captured() and returns: str