feat: remove __version__ cargo cult

[flying-sheep]

__version__ is an old magic spell that has been cargo-culted to modern times without need. Some people even derived more magic from it like __author__, but nothing caught on so tenaciously as __version__.

Much breath has been wasted over purported health benefits such as “performance”. I won’t repeat all that here, just trust me: we shouldn’t propagate this vestige.

People can and should just use importlib.metadata.version('pkgname').

There should be one– and preferably only one –obvious way to do it.

compatibiliy

this is backwards-compatible, as __version__ is neither in the docs nor in __all__ and therefore not a public API.

[github-actions]

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[grst]

While I agree that people should use importlib, there's still a lot of functionality built around this convention.
I don't think it's wrong providing backwards-compatibility with this approach for such a little cost.

[flying-sheep]

There’s only session-info AFAIK, which not only is very old, but also very tenuously maintained (don’t look at its code 😨). I built session-info2 to replace it and it seems to hold up nicely, there has been exactly one bug so far (around .pth handling, was fixed quickly).

[grst]

I thought about it again and came to the conclusion that you are right. If at this point anyone relies on version it's a bug on their end.