20.8
Relicense under both Apache License, v2.0 and a 2 clause BSD license
Update manylinux detection to be robust to incompatible ABIs (#221)
Add tests for new python_version logic
Fix testsuite for pytest 5.x
Deprecate LegacyVersion/LegacySpecifier (#342)
Don't put an underscore in the version portion of Python 3.10 compatibility tags (#355)
Fix `canonicalize_version` to accept Version instances (#328)