Return current playstate of the device.

def state(self):
        """ Return current playstate of the device. """
        if self.is_active:
            if 'NowPlayingItem' in self.session:
                if self.session['PlayState']['IsPaused']:
                    return STATE_PAUSED
                else:
                    return STATE_PLAYING
            else:
                return STATE_IDLE
        else:
            return STATE_OFF