code: def test_list_unification(self):
      def fn():
          return [1, None, 2]
  
      def fn2(x):
          return [torch.ones(2, 2), None, x]
  
      self.checkScript(fn, [])
      self.checkScript(fn2, (torch.ones(2, 2),))
  
imports: import os
  import sys
  import torch
  from torch.testing._internal.jit_utils import JitTestCase, make_global
  from torch.testing._internal.common_utils import IS_WINDOWS
  from collections import namedtuple
  from typing import List, Tuple, Dict, NamedTuple
label_desc: Use image node_id 14 for calling the TestTyping obj's underlying member method code with example usage: obj.test_list_unification() and returns: list, list