This package does not support Python 3.12. Please test it with Python 3.12 as a matter of urgency as the default will change in early June, as per message on gentoo-dev: https://www.mail-archive.com/gentoo-dev@lists.gentoo.org/msg99104.html. Please check the information provided in the tracker. Ask in #gentoo-python on IRC if need any help.
Apologies, I forgot to put it in the commit message but it's fixed now https://github.com/gentoo/gentoo/commit/bd3493ceb54e81958ec407febf85855ad60c8753