middleware test

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

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

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

obj=main()
obj=middle(obj)
obj=middle2(obj)
print obj.func(10)