middleware test 2

MIDDLEWARE = (
    'middle',
    'middle2',
)

class middle():
    def func(self, arg):
        arg *= 2
        return arg

class middle2():
    def func(self, arg):
        arg *= 2
        return arg

class main():
    def func(self, arg):
        return arg*2

arg, obj, f = 10, main(), 'func'
for i in MIDDLEWARE:
    arg = getattr(globals()[i](), f)(arg)
print getattr(obj, f)(arg)