@property
    def master_state(self):
        """Return the master state for entity or None."""
        if self._attrs in CONF_STATE:
            master_state = self._entity_lkp(self._attrs[CONF_STATE][0],
                                            self._attrs[CONF_STATE][1])
            return master_state if master_state else STATE_OFF
        else:
            return None
dataset/ETHPy150Open home-assistant/home-assistant/homeassistant/components/media_player/universal.py/UniversalMediaPlayer.master_state/swapped operands of `in`