Log Message:
py-pykka: updated to 4.2.0

4.2.0

This release has no changes for users, only for distribution packagers.

Changes

Switched build backend from poetry to hatchling.
Switched the docs build from using the toml library to the better maintained \ 
tomli library.
Development is now done using uv and tox-uv, but you should not need uv to \ 
package pykka.
Updated some dev tooling, including ruff and pyright.