code: def test_pickle_types(self, DType):
      # Check that DTypes (the classes/types) roundtrip when pickling
      for proto in range(pickle.HIGHEST_PROTOCOL + 1):
          roundtrip_DType = pickle.loads(pickle.dumps(DType, proto))
          assert roundtrip_DType is DType
  
imports: import functools
  import operator
  import pickle
  import sys
  import types
  from itertools import permutations
  from typing import Any
  from unittest import skipIf
  import pytest
  from pytest import raises
  from torch.testing._internal.common_utils import instantiate_parametrized_tests, parametrize, run_tests, subtest, TEST_WITH_TORCHDYNAMO, TestCase, xpassIfTorchDynamo
  import numpy
label_desc: Use image node_id 3 for calling the TestPickling obj's underlying member method code with example usage: obj.test_pickle_types(DType) without return types