def get_pack_from_index(pack):
 if (not pack):
  raise ValueError('Pack name must be specified.')
 (index, _) = fetch_pack_index()
 return index.get(pack)

def get_pack_from_index ( pack ) : if ( not pack ) : raise ValueError ( 'Pack name must be specified.' ) ( index , _ ) = fetch_pack_index ( ) return index . get ( pack )
search index by pack name .