code: def testIndexed(self):
      disps = [1, 6, 12]
      for mt in datatypes:
          with self.subTest(name=mt.name):
              mt1 = mt.Create_indexed([4] * 3, disps)
              mt2 = mt.Create_indexed_block(4, disps)
              self.check(mt1)
              self.check(mt2)
              dt1 = tonumpy(mt1)
              dt2 = tonumpy(mt2)
              self.check(dt1)
              self.check(dt2)
              self.assertEqual(dt1, dt2)
              mt3 = mt1.Create_indexed([1], [0])
              mt4 = mt2.Create_indexed_block(1, [0])
              self.check(mt3)
              self.check(mt4)
              dt3 = tonumpy(mt3)
              dt4 = tonumpy(mt4)
              self.check(dt3)
              self.check(dt4)
              self.assertEqual(dt3, dt4)
              mt3.Free()
              mt4.Free()
              mt1.Free()
              mt2.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 13 for calling the TestUtilDTLib obj's underlying member method code with example usage: obj.testIndexed() without return types