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Title: gh-132952: Improve Python startup time by ~12% by mdboom · Pull Request #132956 · python/cpython · GitHub

Open Graph Title: gh-132952: Improve Python startup time by ~12% by mdboom · Pull Request #132956 · python/cpython

X Title: gh-132952: Improve Python startup time by ~12% by mdboom · Pull Request #132956 · python/cpython

Description: This improves the time of a no-site.py startup by 12%, i.e. python -c pass -S I'm not strongly of the opinion this should be merged (hence the draft PR), since there are probably all kinds of other places where "lazy importing" could be used to improve startup time that don't improve readability. On the other hand, it's a fairly large regression from 3.13.x that we may want to avoid. Issue: gh-132952

Open Graph Description: This improves the time of a no-site.py startup by 12%, i.e. python -c pass -S I'm not strongly of the opinion this should be merged (hence the draft PR), since there are probably all kinds of ...

X Description: This improves the time of a no-site.py startup by 12%, i.e. python -c pass -S I'm not strongly of the opinion this should be merged (hence the draft PR), since there are probably all kinds...

Opengraph URL: https://github.com/python/cpython/pull/132956

X: @github

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9fc1238 gh-127648: Improve Python startup time by ~12% mdboom Apr 25, 2025 https://github.com/python/cpython/pull/132956/commits/9fc1238a9771b8e864010f8291cfc3113cf166a2
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