Code cleanups (#97)

Co-authored-by: Stan Ulbrych <stan@python.org>

Update changelog (#93)

Update CHANGELOG.md for 2.1.0 release (#88)

Update changelog for 2.0.0 (#41)

Update changelog for 1.3.0 (#31)

Prepare 1.2.1 release (#23)

Prepare 1.2.0 release (#19)