def concat_multi_values(models, attribute):
 return u';'.join((getattr(m, attribute) for m in models if (getattr(m, attribute, None) is not None)))

def concat_multi_values ( models , attribute ) : return u';' . join ( ( getattr ( m , attribute ) for m in models if ( getattr ( m , attribute , None ) is not None ) ) )
format mopidy model values for output to mpd client .