Message 282074 - Python tracker

As of Issue 25701, the null-to-delete feature is documented as being deprecated in favour of calling the related Del functions or macros. There was a python-dev thread at <https://marc.info/?i=n32kch$eie$1@ger.gmane.org>.

I’m not sure if that is good enough, or do we need to e.g. clarify that the deprecation is only at the API (C header) level, and not the ABI level?