Python decorator for static functions and instance methods

decorator.py

# Author: aurzenligl (https://stackoverflow.com/users/7249587/aurzenligl)
# see https://stackoverflow.com/a/48836522/704244
from functools import wraps

def _declassify(fun, args):
    if len(args):
        met = getattr(args[0], fun.__name__, None)
        if met:
            wrap = getattr(met, '__func__', None)
            if getattr(wrap, 'original', None) is fun:
                maybe_cls = args[0]
                cls = maybe_cls if isclass(maybe_cls) else maybe_cls.__class__
                return cls, args[1:]
    return None, args


def decorated(fun):
    desc = next((desc for desc in (staticmethod, classmethod)
                 if isinstance(fun, desc)), None)
    if desc:
        fun = fun.__func__

    @wraps(fun)
    def wrap(*args, **kwargs):
        cls, nonselfargs = _declassify(fun, args)
        clsname = cls.__name__ if cls else None
        print('class: %-10s func: %-15s args: %-10s kwargs: %-10s' %
              (clsname, fun.__name__, nonselfargs, kwargs))

    wrap.original = fun

    if desc:
        wrap = desc(wrap)
    return wrap


class C:
    @decorated
    def f(self, a, b):
        print(a, b)

    @staticmethod
    @decorated
    def g(a, b):
        print(a, b)

    @classmethod
    @decorated
    def h(cls, a, b):
        print(a, b)


C().f(1, 2)
C.g(1, 2)
C.h(1, 2)


class D:
    def g(self):
        pass


class H:
    def h(self):
        pass


C.g(D(), 2)
C.g(H(), 2)