Where should I look in code fixed by AI? Practice verifying with 'small diffs'

I only wanted to fix one place, but the code returned by the AI had its names and structure changed.It might look fine if it ...

Identifying standard library APIs removed in Python 3.15 from your code using AST—502 ...

Python 3.15.0 was released on October 9, 2026. The "Removed" section of the official "What's New in Python 3.15" document ...