• Tuesday, December 16, 2025 Python 3.15.0 alpha 3 This is an early developer preview of Python 3.15 www.python.org/downloads/release/python-3150a3/ Major new features of the 3.15 series, compared to 3.14 Python 3.15 is still in development. • This release, 3.15.0a3, is the third of seven planned alpha releases. • Alpha releases are intended to make it easier to test the current state of new features and bug fixes and to test the release process. • During the alpha phase, features may be added up until the start of the beta phase (2026-05-05) and, if necessary, may be modified or deleted up until the release candidate phase (2026-07-28). • Please keep in mind that this is a preview release and its use isnotrecommended for production environments. • Many new features for Python 3.15 are still being planned and written.
Article Summaries:
- Python 3.15.0 α3 has been released as the third of seven planned alpha builds for the upcoming Python 3.15 series. The preview is aimed at developers testing new features and bug fixes before the beta phase begins on 5 May 2026. Key additions announced include PEP 799, a high‑frequency statistical profiler; PEP 686, which sets UTF‑8 as the default source encoding; and PEP 782, a new C‑API for creating bytes objects. The release also improves error messages. The next alpha, 3.15.0 α4, is scheduled for 13 January 2026. The release is not intended for production use.
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