can't support 5.5.*-mariadb
That's an ancient version of mariadb, first of all. Second of all, it doesn't matter because that version is so old it doesn't support any of the features that the version-check is designed to flip.
https://github.com/coleifer/peewee/blob/cc02d32d05acfdfa2b4d01d99f646b56b6a3c754/peewee.py#L3813