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Title: [wip] Better handling of generics when narrowing by hauntsaninja · Pull Request #20673 · python/mypy · GitHub

Open Graph Title: [wip] Better handling of generics when narrowing by hauntsaninja · Pull Request #20673 · python/mypy

X Title: [wip] Better handling of generics when narrowing by hauntsaninja · Pull Request #20673 · python/mypy

Description: Optional static typing for Python. Contribute to python/mypy development by creating an account on GitHub.

Open Graph Description: Notably we preserve behaviour on the testNarrowingCollections test I added

X Description: Notably we preserve behaviour on the testNarrowingCollections test I added

Opengraph URL: https://github.com/python/mypy/pull/20673

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