code: def test_return_code(self):
      self.assertEqual(os.popen("exit 0").close(), None)
      status = os.popen("exit 42").close()
      if os.name == "nt":
          self.assertEqual(status, 42)
      else:
          self.assertEqual(os.waitstatus_to_exitcode(status), 42)
  
file_path: cpython/Lib/test/test_popen.py
imports: import unittest
  from test import support
  import os, sys
label_desc: Use image node_id 3 for calling the PopenTest obj's underlying member method code with example usage: obj.test_return_code() without return types