Update to python 3.13

[seanbudd]

Related issues, PRs or discussions

None

What is the current state of the codebase?

We have been stuck on python 3.11 due to a bug in py2exe which is now fixed (context: #18449).
We should now be able to update safely to Python 3.13.

Note: Python 3.13 has limited support for Windows 8.1.
We will drop 8.1 support with this upgrade.
python/cpython#98383

Why are changes required?

We need to keep up with the latest python version for security and general reasons

What technical changes are required?

Updating dependencies and python version specifiers in the build system.

• Create dual 3.11/3.13 builds: Build with python 3.13 in parallel #18611
• Mark End of support for Windows 8.1 Support Windows 10 or later #18684
• Update server to not serve 2026.1+ to Win 8.1
• Switch default builds from 3.11 to 3.13 Update to Python 3.13 for 2026.1 #18689
• Update brlapi for 3.13, re-enable unit test for brlapi Update brlapi bindings to support Python 3.13 and X64 #18657
• Consider removing actions/setup-python@v5 from steps
• Update python in other scripts (e.g. crowdin scripts) Update to Python 3.13 for 2026.1 #18689

Are the proposed technical changes API breaking?

Yes

Are there potential risks or issues with the proposed implementation?

Yes, we should perform this early in the 2026.1 release cycle

[seanbudd]

As part of this, we should be able to remove actions/setup-python@v5 steps, as the expected version of python should be installed on github actions

[SaschaCowley]

As part of this, we should be able to remove actions/setup-python@v5 steps, as the expected version of python should be installed on github actions

What about when GitHub Actions upgrades to Python 3.14?

[seanbudd]

What about when GitHub Actions upgrades to Python 3.14?

This shouldn't matter, each windows- image contains a selection of certain python versions pre-downloaded. windows-2025 should never remove python versions, only add new ones. This will only be an issue if a new windows- image is released that doesn't contain 3.13 by default.

[SaschaCowley]

Aah right, cool

[josephsl]

Hi,

Regarding ending support for Windows 8.1: feel free to use the "aqua" branch on my repo (josephsl/nvda) as basis for that work once Python 3.13 upgrade task is initiated. Note that Windows 10 1507 (LTSB) will go out of support in October 2025, so I think we should support 1607 or later (as Server 2016 is the oldest supported Windows Server release from Microsoft); if 1607 is chosen as minimum Windows 10 version, then I recommend basing the work from "aqua16" branch.

Thanks.