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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_quality_options(self, channel):
 """Get the available quality options for streams of the given channel Possible values in the list: * source * high * medium * low * mobile * audio :param channel: the channel or channel name :type channel: :class:`models.Channel` | :class:`str` :returns: list of quality options :rtype: :class:`list` of :class:`str` :raises: :class:`requests.HTTPError` if channel is offline. """

        optionmap = {'chunked': 'source',
                     'high': 'high',
                     'medium': 'medium',
                     'low': 'low',
                     'mobile': 'mobile',
                     'audio_only': 'audio'}
        p = self.get_playlist(channel)
        options = []
        for pl in p.playlists:
            q = pl.media[0].group_id
            options.append(optionmap[q])
        return options