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🏆 Top 5 Python 3.15 features to start using today: 1. Lazy imports 2. New built-in `frozendict` 3. New built-in `sentinel` 4. Unpacking inside comprehensions 5. New sampling profiler Tachyon What's your top Python 3.15 new feature?

I think my top 5 are: 1. UTF-8 as the default encoding on Windows 2. The new sentinel type 3. Unpacking in comprehensions: [*sub for sub in nested] 4. The new sampling profiler 5. pprint's new expand=True But it's hard to choose!

Basically Windows has been reading/writing with an encoding of cp1252 by default for forever. Both it and utf-8 are ASCII supersets but DIFFERENT ones. Valid text in cp1252 can result in errors or emojibake in utf-8 and vice versa. It's a cross-platform mess. And once 3.14 is EOL'd it'll be done.

How can I check for myself that the default encoding on Windows is cp1252 _without_ a Windows machine? Can you help me?

Get someone to copy paste this code into a Python REPL (3.14 and below) on a Windows machine: print(open(__file__).encoding) Bonus points if they do it 3.15 also to see utt-8 shown.

IIRC, look at the docs for open and the notes on the default value for encoding. It mentions some module’s function like sys.getdefaultencoding (making this up!) or some such.

Oh, right. Thanks for the extra context. I'm covering the UTF-8 default in my “15 days of Python 3.15”, but I just wasn't sure why you were so emphatically excited about it :D

Awesome. Summary of my excitement: almost no one specifies encoding="utf-8" in all their open() calls... and now they don't have to! Looking forward to your 15 days of posts!