Regression in tricky __dict__ use.

[felixxm]

Bug report

Bug description:

I noticed a regression in Python 3.13.0 alpha 6. Django LazySettings started to crash because _wrapper is no longer set to the empty sentinel. I bisected this regression to the c32dc47, so it's related with the recent changes in __dict__.

Django's LazySettings and LazyObject are quite tricky. I will try to provide a small reproducer later.

CPython versions tested on:

3.13

Operating systems tested on:

Linux

[ronaldoussoren]

Issue #117750 is likely related to this.

[encukou]

The dict issue is fixed on main (#117808), but the Django tests now fail with another assertion added as part of the same change:

python: ./Include/internal/pycore_object.h:283: _PyObject_Init: Assertion `_PyType_HasFeature(typeobj, Py_TPFLAGS_HEAPTYPE) || _Py_IsImmortal(typeobj)' failed.

cc @markshannon

[markshannon]

Should be fixed by #117673.

[felixxm]

Let me confirm 🕵️‍♂️

[felixxm]

It works for me 🎉 Many thanks for help 🧑‍🚒