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gh-144873: Remove Overzealous `isinstance` Optimization#144874

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George-Ogden wants to merge 3 commits intopython:mainpython/cpython:mainfrom

George-Ogden:gh-144873George-Ogden/cpython:gh-144873Copy head branch name to clipboard

Conversation Commits3 (3)Checks Files changed

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gh-144873: Remove Overzealous `isinstance` Optimization#144874
George-Ogden wants to merge 3 commits intopython:mainfrom
George-Ogden:gh-144873

Commits

Commits on Feb 16, 2026

Add failing test for custom isinstance check
George-Ogden
committed
Remove overzealous isinstance optimization
George-Ogden
committed
Add subclasscheck tests
George-Ogden
committed

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