Python 3.13 came out today: https://docs.python.org/3.13/whatsnew/3.13.html

Datasette does not run under Python 3.13 due to this issue with Pint:

• Python 3.13 error: cannot inherit frozen dataclass from a non-frozen one hgrecco/pint#1969

Options:

• Ship a Datasette 0.x version that marks itself as not working with Python 3.13
• Fork Pint, fix the bug, ship a pint-for-python313 packago to PyPI and ship a Datasette 0.x version that depends on that
• Backport the removal of Pint from 1.0 to 0.x and ship a Datasette 0.x version that no longer has the units feature
• Vendor a fixed version of Pint into the 0.x branch

I like that last option best.