code: def testProbe(self):
      comm = self.COMM.Dup()
      try:
          status = MPI.Status()
          flag = comm.iprobe(MPI.ANY_SOURCE, MPI.ANY_TAG, status)
          self.assertFalse(flag)
          for smess in messages:
              request = comm.issend(smess, comm.rank, 123)
              self.assertIsInstance(request, self.RequestType)
              self.assertTrue(bool(request != MPI.REQUEST_NULL))
              self.assertFalse(bool(request == MPI.REQUEST_NULL))
              self.assertTrue(
                  bool(request == self.RequestType(request))
              )
              self.assertFalse(
                  bool(request != self.RequestType(request))
              )
              self.assertTrue(bool(request != None))
              self.assertFalse(bool(request == None))
              self.assertTrue(bool(request))
              while not comm.iprobe(
                  MPI.ANY_SOURCE, MPI.ANY_TAG, status
              ):
                  pass
              self.assertEqual(status.source, comm.rank)
              self.assertEqual(status.tag, 123)
              comm.probe(MPI.ANY_SOURCE, MPI.ANY_TAG, status)
              self.assertEqual(status.source, comm.rank)
              self.assertEqual(status.tag, 123)
              self.assertTrue(request)
              flag, obj = request.test()
              self.assertTrue(request)
              self.assertFalse(flag)
              self.assertIsNone(obj)
              obj = comm.recv(None, comm.rank, 123)
              self.assertEqual(obj, smess)
              self.assertTrue(request)
              obj = request.wait()
              self.assertFalse(request)
              self.assertIsNone(obj)
      finally:
          comm.Free()
  
imports: from mpi4py import MPI
  from mpi4py.util import pkl5
  import sys, os
label_desc: Use image node_id 16 for calling the BaseTest obj's underlying member method code with example usage: obj.testProbe() without return types