testExceptionCleanupNames() is supposed to test that the local variable bound to the exception instance is only visible inside the except block, and tests that by checking whether the name is in locals(), but it actually deletes the name before that, so it appears it isn't testing what it's supposed to be testing.

```
        try:
            raise Exception()
        except Exception as e:
            self.assertTrue(e)
            del e
        self.assertNotIn('e', locals())
```

I don't know for sure, but maybe it's trying to test "del" interacting with the fact that the "as e" part doesn't escape the "except" clause, unlike normal assignments:

>>> try:
...     raise Exception
... except Exception as e:
...     print('exception raised')
...     foo = 1
...
exception raised
>>> foo
1
>>> e
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'e' is not defined

Perhaps it's testing that the implicit `del` doesn't blow up if the variable is already deleted.

Great point, it's indeed a good thing to test. So I guess the test is just incomplete.

New changeset 82c53229e18f5853c82cb8ab6b9af1925a0e9e58 by Yellow Dusk in branch 'main':
bpo-46442: improve and rename testExceptionCleanupNames (GH-30758)
https://github.com/python/cpython/commit/82c53229e18f5853c82cb8ab6b9af1925a0e9e58

New changeset d4a9e34401d519250d3b3744cd10394069f748c1 by Miss Islington (bot) in branch '3.10':
bpo-46442: improve and rename testExceptionCleanupNames (GH-30758)
https://github.com/python/cpython/commit/d4a9e34401d519250d3b3744cd10394069f748c1

New changeset e064af564c8580285a76199229864ddfb1e50c0f by Miss Islington (bot) in branch '3.9':
bpo-46442: improve and rename testExceptionCleanupNames (GH-30758)
https://github.com/python/cpython/commit/e064af564c8580285a76199229864ddfb1e50c0f

Thanks, @yellowdusk1590!