code: def _get_config(self, host, port, unix_socket, auth, config_key):
          
  
          client = self._client(host, port, unix_socket, auth)
          if client is None:
              return None
  
          config_value = client.config_get(config_key)
          del client
          return config_value
docs: Return config string from specified Redis instance and config key
  
  :param str host: redis host
  :param int port: redis port
  :param str host: redis config_key
  :rtype: str