def track_for_id(track_id):
 for plugin in find_plugins():
  track = plugin.track_for_id(track_id)
  if track:
   (yield track)

def track_for_id ( track_id ) : for plugin in find_plugins ( ) : track = plugin . track_for_id ( track_id ) if track : ( yield track )
fetches a track by its musicbrainz id .