2.8.0 release

[gpotter2]

This issue tracks the upcoming 2.8.0 release.

Expected date: this week (before 05/09 if all goes well)

Deprecation notice

• This major version will be the last to support Python 3.7 and 3.8. While this was initially planned for 2.7.0, support was extended because of how used those versions still are. They have been EoL for more than 2 years, and we highly encourage remaining users to upgrade.

Note

We have clarified our CONTRIBUTING and SECURITY guidelines. This notably includes some new guidance related to the use of AI, and some instructions regarding the submission of security issues. We encourage contributors to take a moment to read the updated versions.

Changelog

TBD XXX TODO

• Work has begun to clean up the remaining compatibility code that allowed the transition from Python 2.