code: def inner_parser(self) -> BaseParser:
          
          if self._inner_parser is not None:
              return self._inner_parser
  
          config = self.client.get(self.endpoint)
          if not config:
              raise KVStorageValueIsEmpty('Key `{0}` does not exist or value is empty'.format(self.endpoint))
  
          config = config.decode()
  
          self._inner_parser = self.inner_parser_class(
              config=io.StringIO(config),
              path_separator=self.path_separator,
              scope=None
          )
          return self._inner_parser
docs: Prepares inner config parser for config stored at ``endpoint``.
  
          :return: an instance of :class:`~django_docker_helpers.config.backends.base.BaseParser`
  
          :raises config.exceptions.KVStorageValueIsEmpty: if specified ``endpoint`` does not contain a config