This was the latest-dated reference I found in the July archives with a relevant subject line.

On July 22, 2022 3:09:36 AM EDT, "Undiscussed Horrific Abuse, One Victim of Many" <gmkarl@gmail.com> wrote:
here's a recent stable code. this was before the 'fiction' approach i
believe; classes could still be hoisted to be subclasses.
https://lists.cpunks.org/pipermail/cypherpunks/attachments/20220716/dec3d2ee/attachment-0001.py