code: def testAlignmentStruct(self):
      off = MPI.DOUBLE.extent
      structtype = MPI.Datatype.Create_struct(
          [1, 1],
          [0, off],
          [MPI.INT, MPI.DOUBLE],
      )
      alignment = MPI._typealign(structtype)
      self.assertIsNone(alignment)
      structtype.Free()
  
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 24 for calling the TestUtilDTLib obj's underlying member method code with example usage: obj.testAlignmentStruct() without return types