- Update to v6.0
* support and test against Python 3.9 and Django 3.1/3.2
* added custom serializers support (thx to Arcady Usov)
* support callable extra in @cached_as() and friends
* made simple cache obey prefix
* skip JSONFields for purposes of invalidation
* configure skipped fields by internal types, classes still supported
* handle `DatabaseError` on transaction cleanup (Roman Gorbil)
* do not query old object if cacheops is disabled
* do not fetch deferred fields during invalidation, fixes #387
Backwards incompatible changes:
* callable `extra` param, including type, now behaves differently
* simple cache now uses prefix