code: def makeStruct(self, dt, mt):
      dt = numpy.dtype(dt).str
      stp = numpy.dtype(",".join(["B", dt, "B"]), align=True)
      off = lambda i: stp.fields[stp.names[i]][1]
      blens = [1, 1, 1]
      disps = [0, off(1), off(2)]
      types = [MPI.BYTE, mt, MPI.BYTE]
      mtp = MPI.Datatype.Create_struct(blens, disps, types)
      return stp, mtp
  
imports: from mpi4py import MPI
  from mpi4py.util.dtlib import from_numpy_dtype
  from mpi4py.util.dtlib import to_numpy_dtype
  import sys, os
  import itertools
label_desc: Use image node_id 8 for calling the TestUtilDTLib obj's underlying member method code with example usage: obj.makeStruct(dt, mt) and returns: stp,  mtp