fix: Add type annotations to `get_object_or_None()`

[tylerlaprade]

Fixes #103

Test plan

Pyright recognizes a Model type

Pyright rejects a non-model type

Pyright rejects an instance of a model in place of the type

Pyright accepts a BaseManager

Pyright accepts a QuerySet

[skorokithakis]

Sorry for the delay! Which versions does this work with? Would you mind changing the supported versions in the setup file?

[tylerlaprade]

Sure, happy to do that, ~just not sure where to look~!

EDIT: I found setup.py. It seems out of date, as the latest Python version it lists is 3.6, while the latest stable version is 3.12.2. Type hints were first introduced in 3.5, but were a bit clunky. If we want to continue supporting older versions, we might need to find some workarounds to get the older versions to ignore new syntax.

[skorokithakis]

I'm fine to drop support for older versions and only support 3.6+, but there's a specifier you use in the setup.py to tell it which Python versions you want to support, and I don't remember the syntax offhand. Would you happen to remember what I'm talking about?

[tylerlaprade]

As far as I can tell, 'Programming Language :: Python :: 3.XX', is all we need in setup.py.

However, I just tested and found that this simpler syntax for generic types only became available in Python 3.12. If we want to support 3.10 and 3.11, we'd have to change it to use the older TypeVar syntax, like so: T = TypeVar('T', bound=CondorBaseModel).

To go earlier than 3.9, we'd have to change the union type syntax of the return type from T | None to Union[T, None] (I'm still trying to confirm if this is right). This would give us 3.5-3.9.

To go all the way back to 3.0, we would simply have to replace from typing import TypeVar with from typing_extensions import TypeVar. If we're already making the switch to TypeVar, this wouldn't be a big deal.

I have not checked what it would take to maintain Python 2.0 compatibility, but I can look it up if desired.

[skorokithakis]

I think 3.5+ is fine, anything past that might be a bit too new. I don't mean the trove classifier, I meant the python_requires directive.

[tylerlaprade]

Hi, sorry for the delay, I was on paternity leave. I believe this addresses all the problems.