Python 3.15 released: sentinel, frozendict, UTF-8 by default and JIT improvements

Python 3.15, a programming language release, has been released. According to the source text, notable changes include the addition of the built-in sentinel and frozendict types, UTF-8 encoding by default, configuration files for package initialization, and improvements to the experimental JIT compiler. The source records the publication date as 9 October 2026. The text does not detail each feature; it points to the article "What's new in Python 3.15" on LWN for a detailed analysis and to the changelog for the full list of changes. To verify the content, find the original article by the title given in the source and consult the 3.15 changelog in the official Python documentation. This release mainly interests development teams that maintain Python code, since the default encoding change and package initialization files may affect existing scripts and environments. Before adopting the version, test your application in a separate environment. This item is a news record about a programming language and does not directly address privacy or AI.