Bug report

Bug description:

I tried to search for a related ticket by various queries but did not find any, hopefully I haven't overlooked it.

While rewriting a codebase fromOptional[foo] to the newerfoo | None style, I encountered thatthreading.Lock does not allow the latter.

Example on MacOS 3.12.1:

>>>fromtypingimportOptional>>>fromthreadingimportLock>>>Optional[Lock]typing.Optional[<built-infunctionallocate_lock>]>>>Lock|NoneTraceback (mostrecentcalllast):File"<stdin>",line1,in<module>TypeError:unsupportedoperandtype(s)for|:'builtin_function_or_method'and'NoneType'

Given that the documentation states the following, the error makes sense:

Note that Lock is actually a factory function which returns an instance of the most efficient version of the concrete Lock class that is supported by the platform.

I actually didn't know it was a factory function. I would not intentionally create a<function> | None type. But since the documentation describesthreading.Lock as a class, one would expect to be able to use it as any other type.

CPython versions tested on:

3.11, 3.12, 3.13.0a3

Operating systems tested on:

Linux, macOS

Linked PRs

• gh-114315: Makethreading.Lock a real class, not a factory function #114479