code: def testCreateFromGroup(self):
      group = self.COMM.Get_group()
      try:
          comm = MPI.Intracomm.Create_from_group(group)
      except NotImplementedError:
          self.assertLess(MPI.VERSION, 4)
          self.skipTest("mpi-comm-create_from_group")
      except MPI.Exception as exc:  # openmpi
          UNSUPPORTED = MPI.ERR_UNSUPPORTED_OPERATION
          if exc.Get_error_class() != UNSUPPORTED:
              raise
      else:
          ccmp = MPI.Comm.Compare(self.COMM, comm)
          comm.Free()
          self.assertEqual(ccmp, MPI.CONGRUENT)
      finally:
          group.Free()
  
imports: from mpi4py import MPI
  import mpiunittest
label_desc: Use image node_id 16 for calling the BaseTestComm obj's underlying member method code with example usage: obj.testCreateFromGroup() without return types