pythonPackages.{pep,flake8}: undo changes from #19104

[groxxda]

Motivation for this change

This change introduces breakage because pycodestyle and pep8 are not API compatible and packages have not yet been updated.
The packages that are compatible should be converted to use pycodestyle on a per-package basis.

Introduced in #19104
That PR also updates flake8 which breaks stuff.

This fixes virtmanager.

CC @mbld @Mic92 @garbas

Things done

• Tested using sandboxing
  (nix.useSandbox on NixOS,
  or option build-use-sandbox in nix.conf
  on non-NixOS)
• Built on platform(s)
  • NixOS
  • OS X
  • Linux
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.

---

This reverts commit 0986a17.

[mention-bot]

@groxxda, thanks for your PR! By analyzing the annotation information on this pull request, we identified @FRidh to be a potential reviewer

[FRidh]

yep that PR shouldn't have been merged.

[FRidh]

can you undo flake8 as well?

[groxxda]

@FRidh done
built python35Packages.flake8{_3}
Let me know if the package should have an other name. Also flake8_3 lacks a maintainer as I'm not sure whether @garbas want's to maintain it.

Please don't squash merge 😉

[groxxda]

oh, looks like mccabe also needs reverting..

[groxxda]

i'll post a follow up pr in a minute

[FRidh]

@groxxda done in 25dcdc5

[groxxda]

@FRidh sorry I somehow forgot to file the pr after hours of rebuilding 😞