Ash Framework: variable assignment mistake (page 38)

In the “Defining an update action” section
artist = Tunez.Music.get_artist_by_id!(​"​​an-artist-id"​)
should be:
{:ok, artist} = Tunez.Music.get_artist_by_id!(​"​​an-artist-id"​)

Otherwise the next line will fail with an error about resource ID