code: def unregister_option(self, option):
      splits = option.split(".")
      conf = self._config
      for name in splits[:-1]:
          config = conf.get(name)
          if not isinstance(config, dict):
              raise AttributeError(
                  f"Fail to unregister option: {option}, conflict has encountered"
              )
          else:
              conf = config
  
      key = splits[-1]
      if key not in conf:
          raise AttributeError(
              f"Option {option} not configured, thus failed to unregister."
          )
      conf.unregister(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 7 for calling the Config obj's underlying member method code with example usage: obj.unregister_option(option) without return types