'Choose how to add new artists to the title and set the new
metadata. Also, print out messages about any changes that are made.
If `drop_feat` is set, then do not add the artist to the title; just
remove it from the artist field.'

def update_metadata(self, item, feat_part, drop_feat):

    self._log.info(u'artist:    {0}    ->    {1}', item.artist, item.albumartist)
    item.artist = item.albumartist
    if item.artist_sort:
        (item.artist_sort, _) = split_on_feat(item.artist_sort)
    if ((not drop_feat) and (not contains_feat(item.title))):
        feat_format = self.config['format'].as_str()
        new_format = feat_format.format(feat_part)
        new_title = u'{0}    {1}'.format(item.title, new_format)
        self._log.info(u'title:    {0}    ->    {1}', item.title, new_title)
        item.title = new_title
