code: def get_attribute_at(config, target_path, key, default_value=None):
      
      for target in target_path:
          config = config[target]
      return config[key] if key in config else default_value
docs: Return attribute value at a given path
  
      :param config:
      :param target_path:
      :param key:
      :param default_value:
      :return: