Metaclass wrapping each function call with an argument printer

meta_debug.py

from functools import wraps


def printer(f):
    @wraps(f)
    def wrapper(*args, **kwargs):
        print(args)
        return f(*args, **kwargs)
    return wrapper


class MyMeta(type):
    def __new__(meta, name, bases, dct):
        for k, v in dct.iteritems():
            if callable(v):
                v = printer(v)
                dct[k] = v
        return super(MyMeta, meta).__new__(meta, name, bases, dct)


class Foo(object):
    __metaclass__ = MyMeta

    def double(self, x):
        return x * 2