I can reproduce this locally. How has this not being spotted by the CI:
❯ ./python.exe -m test test_descr
Run tests sequentially
0:00:00 load avg: 3.82 [1/1] test_descr
test test_descr failed -- Traceback (most recent call last):
File "/Users/pgalindo3/github/cpython/Lib/test/test_descr.py", line 4341, in test_vicious_descriptor_nonsense
self.assertEqual(c.attr, 1)
File "/Users/pgalindo3/github/cpython/Lib/test/test_descr.py", line 4328, in __eq__
del C.attr
AttributeError: attr
test_descr failed
== Tests result: FAILURE ==
1 test failed:
test_descr
Total duration: 2 sec 437 ms
Tests result: FAILURE