Last year I learned about Byte Order Mark (BOM), and how imports of CSV files generated on Windows should be decoded as “utf-8-sig” instead of “utf-8” when using Python `csv.reader()`.
That lesson saved me a lot of time today.
Extra background info courtesy of 
@jscholesJames Scholes:
> “The wider issue is that many Python programs are written with no explicit `encoding` argument in `open` calls, implicitly expecting UTF-8 because that's often the default on Unix systems. But it usually is not the default on Windows.”
> “As I understand it, that's set to change in Python 3.15:”
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