AI IntelligenceNov 2, 2026Practical Tip
Article
Simon Willison reports occasional confusing Python dependency errors after switching to Python 3.15…
…where a leftover uv.lock file pins a dependency version that lacks a Python 3.15 wheel (example: watchfiles==1.1.1 failing to build because PyO3's maximum supported version is 3.14).
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AI-generatedSource: Simon Willison
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Source Brief
Simon Willison reports occasional confusing Python dependency errors after switching to Python 3.15, where a leftover uv.lock file pins a dependency version that lacks a Python 3.15 wheel (example: watchfiles==1.1.1 failing to build because PyO3's maximum supported version is 3.14).
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Practical Tip
If you hit a confusing dependency error, delete the uv.lock file and re-run your command (e.g. uv run pytest); Willison says this usually fixes the problem.
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