'Pass a musicbrainz id to this function (either ArtistID or AlbumID)'

def get_artwork_from_cache(self, ArtistID=None, AlbumID=None):

    self.query_type = 'artwork'
    if ArtistID:
        self.id = ArtistID
        self.id_type = 'artist'
    else:
        self.id = AlbumID
        self.id_type = 'album'
    if (self._exists('artwork') and self._is_current(filename=self.artwork_files[0])):
        return self.artwork_files[0]
    else:
        self._update_cache()
        if (self.artwork_errors and self.artwork_url):
            return self.artwork_url
        elif self._exists('artwork'):
            return self.artwork_files[0]
        else:
            return None
