code: def unregister(self, key):
      del self[key]
  
imports: import contextlib
  import functools
  import operator
  import os
  import warnings
  import threading
  from copy import deepcopy
  from typing import Union, Dict
label_desc: Use image node_id 6 for calling the AttributeDict obj's underlying member method code with example usage: obj.unregister(key) without return types