A flake8 plugin that checks for default arguments like:

def default(key=value):
    ...

Positional parameters can unintentionally override these arguments. Instead use the safer kw-only argument equivalent:

def kw_only(*, key=value):
    ...

Install with pip:

$ pip install flake8-kw-only-args

You can check that flake8 has picked it up by looking for flake8-kw-only-args in the output of --version:

$ flake8 --version
2.6.2 (pycodestyle: 2.0.0, flake8-kw-only-args: 1.0.0, pyflakes: 1.2.3, mccabe: 0.5.0) CPython 2.7.11+ on Linux

This plugin add new flake8 warning:

• K801: non-kw-only argument

• Python 3.x (tested on 3.5, 3.6, and 3.7)
• flake8 or pycodestyle

• PEP 3102 -- Keyword-Only Arguments

BSD license