human
I wrote the below code

    def show_album(artist, album):
        if artist:
            album_description = (u'                %s    -    %s' % (artist, album))
        elif album:
            album_description = (u'                %s' % album)
        else:
            album_description = u'                (unknown    album)'
        print_(album_description)
    def format_index(track_info):
        'Return    a    string    representing    the    track    index    of    the    given\n                                TrackInfo    or    Item    object.\n                                '
        if isinstance(track_info, hooks.TrackInfo):
            index = track_info.index
            medium_index = track_info.medium_index
            medium = track_info.medium
            mediums = match.info.mediums
        else:
            index = medium_index = track_info.track
            medium = track_info.disc
            mediums = track_info.disctotal
        if config['per_disc_numbering']:
            if (mediums > 1):
                return u'{0}-{1}'.format(medium, medium_index)
            else:
                return six.text_type((medium_index or index))
        else:
            return six.text_type(index)
    if ((cur_artist != match.info.artist) or ((cur_album != match.info.album) and (match.info.album != VARIOUS_ARTISTS))):
        (artist_l, artist_r) = ((cur_artist or ''), match.info.artist)
        (album_l, album_r) = ((cur_album or ''), match.info.album)
        if (artist_r == VARIOUS_ARTISTS):
            (artist_l, artist_r) = (u'', u'')
        (artist_l, artist_r) = ui.colordiff(artist_l, artist_r)
        (album_l, album_r) = ui.colordiff(album_l, album_r)
        print_(u'Correcting    tags    from:')
        show_album(artist_l, album_l)
        print_(u'To:')
        show_album(artist_r, album_r)
    else:
        print_(u'Tagging:\n                {0.artist}    -    {0.album}'.format(match.info))
    if match.info.data_url:
        print_((u'URL:\n                %s' % match.info.data_url))
    info = []
   ...

What's a good function header?
 ... Here's a good function header?
assistant
#Here's a good function header.

def show_change(cur_artist, cur_album, match):