code: def _check_output(self, script_name, exit_code, out, err):
      if verbose > 1:
          print("Output from test script %r:" % script_name)
          print(repr(out))
      self.assertEqual(exit_code, 0)
      self.assertEqual(err.decode("utf-8"), "")
      expected_results = "%s -> [1, 4, 9]" % self.start_method
      self.assertEqual(out.decode("utf-8").strip(), expected_results)
  
imports: from test import support
  from test.support import import_helper
  import importlib
  import importlib.machinery
  import unittest
  import sys
  import os
  import os.path
  import py_compile
  from test.support import os_helper
  from test.support.script_helper import make_pkg, make_script, make_zip_pkg, make_zip_script, assert_python_ok
  import multiprocess
label_desc: Use image node_id 2 for calling the MultiProcessingCmdLineMixin obj's underlying member method code with example usage: obj._check_output(script_name, exit_code, out, err) without return types