On 31 December 2017 at 19:24, Yahya Abou 'Imran via Python-ideas <python-ideas@python.org> wrote:

>I guess a PR to fix the registry output would make sense (first file a bug on bugs.python.org for it).

Ok, I will!

Please don't hurry with this. I am going to rewrite ABCMeta in C soon.

In fact most of the work is done but I am waiting for implementation of PEP 560 to settle (need few more days for this).

In the C version the caches/registry will be simpler and will not use WeakSet (instead they will be thin C wrappers around normal sets).

Ivan