code: def check_update(self, klass, dict):
      #
      #  This exercises d.update(), len(d), d.keys(), k in d,
      #  d.get(), d[].
      #
      weakdict = klass()
      weakdict.update(dict)
      self.assertEqual(len(weakdict), len(dict))
      for k in weakdict.keys():
          self.assertIn(
              k, dict, "mysterious new key appeared in weak dict"
          )
          v = dict.get(k)
          self.assertIs(v, weakdict[k])
          self.assertIs(v, weakdict.get(k))
      for k in dict.keys():
          self.assertIn(
              k, weakdict, "original key disappeared in weak dict"
          )
          v = dict[k]
          self.assertIs(v, weakdict[k])
          self.assertIs(v, weakdict.get(k))
  
imports: import copy
  import gc
  import random
  import threading
  import unittest
  import torch
  from torch.testing._internal.common_utils import find_library_location, IS_FBCODE, IS_MACOS, IS_SANDCASTLE, IS_WINDOWS, run_tests, TestCase
  from torch.utils.weak import _WeakHashRef, WeakIdKeyDictionary
label_desc: Use image node_id 7 for calling the WeakTest obj's underlying member method code with example usage: obj.check_update(klass, dict) without return types