import sys if not sys.is_gil_enabled(): print("Running in free-threaded mode (PEP 703)") Small, but signals that no-GIL is moving toward official API status. Python 3.13.1 is exactly what a .1 release should be: boring, safe, and necessary . The core team used the month after 3.13.0 to grind through regression reports, fuzzer crashes, and build farm failures.

Here’s a deep-dive post on the topic, written as if from a tech journalist or Python core developer enthusiast. On November 19, 2025, the Python Steering Council and core development team quietly released Python 3.13.1 , the first bugfix release of the 3.13 series. No fireworks, no PEP 8000-level drama — but for anyone running Python in production, teaching it, or building tools, this is the version you’ve been waiting for.

python3.13 --version # Python 3.13.1 python.org/downloads/release/python-3131 (available since Nov 19, 2025)