Simon Willison’s Weblog

String types in Python 3. bytes are now immutable (just like the bytestrings they are replacing) and a new mutable buffer type has been introduced.

Posted 9th October 2007 at 2:08 am

Recent articles

Useful patterns for building HTML tools - 10th December 2025
Under the hood of Canada Spends with Brendan Samek - 9th December 2025
Highlights from my appearance on the Data Renegades podcast with CL Kao and Dori Wilson - 26th November 2025

buffers 2 bytes 1 bytestrings 2 python 1211 python3 21 strings 5 unicode 29

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