code: def _get(self, key):
          
          for conf in self.configs:
              if key in conf:
                  return conf[key]
  
          raise ConfigKeyNotFoundError(key)
docs: Iterate over all the config dictionaries that have been loaded into the list of configs. If value is found,
          immediately return it. Otherwise, raise a ConfigKeyNotFoundError with an appropriate message.
          :param key: The variable to search for in the possible list of configs.
          :return: The corresponding value of the key if found.