code: def deep_update_dict(default, options):
      
      for key in options.keys():
          default_setting = default.get(key)
          new_setting = options.get(key)
          if isinstance(default_setting, dict):
              deep_update_dict(default_setting, new_setting)
          else:
              default[key] = new_setting
docs: Updates the values in a nested dict, while unspecified values will remain
      unchanged