def tour(self, action='start', channel=0, start=True, tour_path_number=1):
        """
        Params:
            action              - start or stop
            channel             - channel number
            start               - True (StartTour) or False (StopTour)
            tour_path_number    - tour path number
        """
        ret = self.command(
            'ptz.cgi?action={0}&channel={1}&code={2}Tour&arg1={3}'
            '&arg2=0&arg3=0&arg4=0'.format(
                action, channel, 'Start' if start else 'Stop',
                tour_path_number)
        )
        return ret.content.decode('utf-8')