__getattr__ on a class and not (or as well as) an instance

Question

I know I can write code like:

class A :
    def __getattr__ (self, name) :
        return name

to trap access to undefined attributes on an

Answer 1

Yes you can. Metaclasses are the answer.

class MyMetaclass(type):
    def __getattr__(cls, name):
        return "cls.%s" % name


class A :
    __metaclass__ = MyMetaclass
    def __getattr__ (self, name) :
        return name

print A().ATTR
print A.ATTR

will output

ATTR
cls.ATTR