v0.4.1

This release mostly targets coverage and testing.

Feature

• Add walk_nodes. (6375de8)
• Support 3.11. (07586c1)

Coverage and testing

• Update CI. (c322763)
• Update tests, minor cleanup. (d4d42a4)
• Add legacy python version tests. (fc60da0)
• Test multiple python versions. (49f4dc4)
• Add code coverage tests. (8922a90, 1ced7ab, a34d048, 752e874)