Rules to check and implement:

General

• no nested functions
• no nested classes (Meta as whitelist)
• no unused arguments
• no len(x) == 0 in if conditions
• no always True checks
• no raise (without new exception) not within except
• no raise NotImplemented
• no __author__
• no / linebrakes

Complexity

• too many local variables
• too many arguments
• too many branches
• too many returns
• too many expressions
• too many statements
• too deep nesting

Function calls

• no exec, eval, and compile
• no vars(), no dir()
• no print, pprint
• no input
• no globals(), no locals()
• no short function names

Keywords

• no global, no nonlocal, no del, no pass

Imports

• no from some import * aka star-import
• no from .. import some aka dot import
• no nested imports
• no __import__

Classes

• no return/yield in __init__
• no self override
• self is not used
• first method argument must be cls or self if not staticmethod
• too few public method (__init__ + one other)
• too many public methods
• too many instance attributes
• no magic methods: __del__
• no attributes with default None: class Fixture: some_attribute = None

Variables

• no blacklist variable names: data, result
• no short variable names

Files

• no bom
• no long files, max-file-lines = 600
• no logic in __init__.py
• no __{}__ filenames, except __init__ and __main__

mypy

• follow this pattern: x: List[SomeValue] = [], def cast(element: Element = None) -> str: