bpo-44655: Include the name of the type in unset __slots__ attribute errors (GH-27199) (GH-27201)

(cherry picked from commit f783428a2313a729ca8b539c5a86ff114b9ff375)

Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>

Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>
3 files changed