'Returns the track that will be played if calling
:meth:`mopidy.core.PlaybackController.previous()`.
For normal playback this is the previous track in the tracklist. If
random and/or consume is enabled it should return the current track
instead.
:param tl_track: the reference track
:type tl_track: :class:`mopidy.models.TlTrack` or :class:`None`
:rtype: :class:`mopidy.models.TlTrack` or :class:`None`'

def previous_track(self, tl_track):

    deprecation.warn(u'core.tracklist.previous_track', pending=True)
    ((tl_track is None) or validation.check_instance(tl_track, TlTrack))
    if (self.get_repeat() or self.get_consume() or self.get_random()):
        return tl_track
    position = self.index(tl_track)
    if (position in (None, 0)):
        return None
    return self._tl_tracks[(position - 1)]
