code: def _redis_connection_settings(self):
          
          return {config.HOST: self.settings.get(config.HOST, self._REDIS_HOST),
                  config.PORT: self.settings.get(config.PORT, self._REDIS_PORT),
                  'selected_db': self.settings.get(config.DB, self._REDIS_DB)}
docs: Return a dictionary of redis connection settings.