函数装饰器可以通过尝试访问一个对象来创建一个新属性吗？

Question

通过装饰器以如下所示的方式包装的方法引用不具有所述属性的对象的属性的行为怎么可能起作用而不是抛出 AttributeError？

class GhostObj:
    def __init__(self):
        self.dummy = 1

    def get_attrs(self):
        return ','.join([f"{attr}" for attr in dir(self) if not attr.startswith('__')])

class Test:
    to_prove_a_point = 1

    def for_all_ghosts(f):
        def wrp(self, *args,**kwargs):
            for go in self.ghosts:
                f(self, go, *args, **kwargs)
        return wrp

    def __init__(self):
        self.ghosts = [GhostObj() for i in range(2)]

    @for_all_ghosts
    def make_ghost_attr(self, go: GhostObj):
        print(go.get_attrs())
        if Test.to_prove_a_point == 1:
            go.should_not_exist = 1
        else:
            go.neither_should_this = 1
        Test.to_prove_a_point = 2
        print(go.get_attrs())


case = Test()
case.make_ghost_attr()

输出：

dummy,get_attrs
dummy,get_attrs,should_not_exist
dummy,get_attrs
dummy,get_attrs,neither_should_this