code: def testProbe(self):
      comm = self.COMM.Dup()
      try:
          request = comm.Issend([None, 0, MPI.BYTE], comm.rank, 123)
          self.assertTrue(request)
          status = MPI.Status()
          comm.Probe(MPI.ANY_SOURCE, MPI.ANY_TAG, status)
          self.assertEqual(status.source, comm.rank)
          self.assertEqual(status.tag, 123)
          self.assertTrue(request)
          flag = request.Test()
          self.assertTrue(request)
          self.assertFalse(flag)
          comm.Recv([None, 0, MPI.BYTE], comm.rank, 123)
          self.assertTrue(request)
          flag = False
          while not flag:
              flag = request.Test()
          self.assertFalse(request)
          self.assertTrue(flag)
      finally:
          comm.Free()
  
imports: from mpi4py import MPI
  import mpiunittest
  import itertools
  import arrayimpl
label_desc: Use image node_id 11 for calling the BaseTestP2PBuf obj's underlying member method code with example usage: obj.testProbe() without return types