I'm afraid you are mistaken here. PEP 8 reads "Arguments on first line forbidden when not using vertical alignment." flake8 does report this, but if it did not,

I'm afraid you are mistaken here. PEP 8 reads "Arguments on first line forbidden when not using vertical alignment." flake8 does report this, but if it did not, that would simply be a bug in flake8. edit: if there are bugs in PEP 8, work to get them fixed rather than promoting alternative styles like the Google style, please!