Currently, the Python versions defined in our CI workflows are defined by passing a static list of envs to .github/workflows/tox.yml. These need to be manually updated when 1) new Python versions are released as latest, and 2) we drop support for old versions of Python.

Possibly as an alternative to envs:, we could add a flag (supported_pythons?) that does the following:

1. retrieve the oldest and latest major versions of Python supported by the project, based on pins in pyproject.toml project.requires-python
   • to start, this only needs to consider the metadata of the top-level project, but perhaps we could also scan dependencies?
2. build a matrix on-the-fly of each major version of Python between the oldest and latest. For instance, if the oldest supported version of the package is Python 3.11, and the latest is Python 3.14, then the test matrix would be 3.11, 3.12, 3.13, 3.14