python 3.11 doesn't like when a mixin overrides a dunder method like __str__, for some reasons it keep using Enum.__str__, see https://github.com/fonttools/fonttools/pull/2655
python 3.11 doesn't like when a mixin overrides a dunder method like __str__, for some reasons it keep using Enum.__str__, see https://github.com/fonttools/fonttools/pull/2655