def art_for_asin(album):
 if album.asin:
  for index in AMAZON_INDICES:
   (yield (AMAZON_URL % (album.asin, index)))

def art_for_asin ( album ) : if album . asin : for index in AMAZON_INDICES : ( yield ( AMAZON_URL % ( album . asin , index ) ) )
generate urls using amazon id string .