- artists_ids = set([row[0] for row in connection.execute(
- "SELECT id FROM artists")])
- artist_2_artist_ids = set([row[0] for row in connection.execute(
- "SELECT artist FROM black_list")] +
- [row[0] for row in connection.execute(
- "SELECT artist FROM albums")] +
- [row[0] for row in connection.execute(
- "SELECT artist FROM tracks")])
+ artists_ids = {row[0] for row in connection.execute(
+ "SELECT id FROM artists")}
+ artist_2_artist_ids = {row[0] for row in connection.execute(
+ "SELECT artist FROM black_list")} | {
+ row[0] for row in connection.execute(
+ "SELECT artist FROM albums")} | {
+ row[0] for row in connection.execute(
+ "SELECT artist FROM tracks")}