Add some missing Self return annotations in redis

[wookie184]

Add some missing Self return annotations in redis

Source for Monitor.__aenter__:
https://github.com/redis/redis-py/blob/e39c7babdd80ecdd930bed9d201e8fb9187309ac/redis/asyncio/client.py#L571

Source for PubSub.__aenter__:
https://github.com/redis/redis-py/blob/e39c7babdd80ecdd930bed9d201e8fb9187309ac/redis/asyncio/client.py#L671

The non-async equivalents already seem to be correct (e.g.

typeshed/stubs/redis/redis/client.pyi

Line 343 in b316dd9

def __enter__(self: Self) -> Self: ...

)

[AlexWaygood]

Thanks! We're not yet able to use typing(_extensions).Self due to lack of mypy support, so we currently use _typeshed.Self instead. _typeshed.Self is just a normal TypeVar, so you have to annotate the parameter as well as the return type:

[AlexWaygood]

(Mypy already has support for typing(_extensions).Self on the master branch; we're just waiting for version 1.0 to be released.)

[AlexWaygood]

Thank you!

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉