could you rename the commit to python3Packages.packet-python: 1.37.1 -> 1.38.2.
This should trigger the build.

python3Packages or pythonPackages?

@teto ping on the name clarification please. Is there a place where python (and other) modules commit messages format is described? The manual's direction looks like a subset.

So why python3Packages vs just pythonPackages or what I think makes the most sense actually: python.pkgs.packet-python:...

It should have been in the https://github.com/NixOS/nixpkgs/blob/master/.github/CONTRIBUTING.md but the explanation is not good, I will try to update it. Meanwhile you can grep the repostiory log and you will see pythonPackages.XXX at the start.
If it works with both python 2 and 3, use pythonPackages else python3Packages. Both are an alias to python.pkgs so I suppose they are here to provide some abstraction over the underlying implementation.

yep I've seen all three flavors. IMO python.pkgs would make more sense for 2&3 compatible packages since pythonPackages.$foo refers to the python2 version atm and python3Packages is python3, so there doesn't seem to be one prefix to indicate both versions well. But, this is probably not the place to change convention :D.

🎉