code: def test_success(self):
      mp.start_processes(
          _test_success_func, nprocs=2, start_method=self.start_method
      )
  
imports: import os
  import pickle
  import random
  import signal
  import sys
  import time
  import unittest
  from torch.testing._internal.common_utils import TestCase, run_tests, IS_WINDOWS, NO_MULTIPROCESSING_SPAWN
  import torch.multiprocessing
label_desc: Use image node_id 1 for calling the _TestMultiProcessing obj's underlying member method code with example usage: obj.test_success() without return types