__setattr__ class decorator python

Question

I'm using a class decorator but I didn't understand how set attribute with setattr, this is my code:

def cldecor(*par):
    def onDecorator(aClass):
        class wrapper:
            def __init__(self, *args): 
                self.wrapped = aClass(*args)
            def __getattr__(self, name): 
                return getattr(self.wrapped, name)
            def __setattr__(self, attribute, value): 
                if attribute == 'wrapped': 
                    self.__dict__[attribute] = value 
                else:
                    setattr(self.wrapped, attribute, value)
        return wrapper
    return onDecorator


@cldecor('data','size')
class Doubler:
    def __init__(self,label,start):
        self.label = label
        self.data = start

    def display(self):
        print('{0} => {1}'.format(self.label, self.data))

but when i do:

if __name__ == "__main__":
    X = Doubler('X is ', [1,2,3])
    X.xxx = [3,4,9]
    print(X.xxx)
    X.display()

i have this output:

[3, 4, 9]
X is  => [1, 2, 3]

how can i do for having this output?

[3, 4, 9]
X is  => [3, 4, 9]