Add a direct dependency on typing-extensions

[musicinmybrain]

Since typing_extensions is directly and unconditionally imported,

sqlmodel/sqlmodel/main.py

Line 53 in e495ebe

from typing_extensions import deprecated

sqlmodel/sqlmodel/orm/session.py

Line 20 in e495ebe

from typing_extensions import deprecated

sqlmodel/sqlmodel/ext/asyncio/session.py

Line 20 in e495ebe

from typing_extensions import deprecated

sqlmodel/sqlmodel/sql/_expression_select_cls.py

Line 9 in e495ebe

from typing_extensions import Self

we should not rely on an indirect dependency via pydantic.

The minimum version, 4.5.0, was chosen as the first release that included both typing_extensions.Self and typing_extensions.deprecated.

[github-actions]

📝 Docs preview

Last commit 76915f2 at: https://ddf1c8d6.sqlmodel.pages.dev

[svlandeg]

Hi, thanks for the PR!

I agree that we shouldn't rely on indirect dependencies for external libraries that we're importing directly.

We can either follow the route this PR proposes and add typing-extensions to the dependencies, or we could install it only conditionally for older versions of Python, and use typing whenever we can. If I'm not mistaken, Python 3.13+ has deprecated in typing, for Self it's Python 3.11 and upwards. So if we use _compat to import from either depending on the Python version, we'd only have to install typing-extensions for Python 3.10, 3.11 and 3.12.

Then again, we'd gain very little as typing-extensions would still be installed by pydantic on any Python version 🤷. So maybe the solution in this PR is just the easiest one.

@YuriiMotov: do you have an opinion?

I'll tentavily approve this in the meantime 🙂