code: def testPickle(self):
      from pickle import dumps, loads
  
      for errhandler in [
          MPI.ERRHANDLER_NULL,
          MPI.ERRORS_ARE_FATAL,
          MPI.ERRORS_RETURN,
          MPI.ERRORS_ABORT,
      ]:
          if not errhandler:
              continue
          errh = loads(dumps(errhandler))
          self.assertIs(errh, errhandler)
          errh = loads(dumps(MPI.Errhandler(errhandler)))
          self.assertIsNot(errh, errhandler)
          self.assertEqual(errh, errhandler)
  
imports: from mpi4py import MPI
  import mpiunittest
label_desc: Use image node_id 2 for calling the TestErrhandler obj's underlying member method code with example usage: obj.testPickle() without return types