How to use the sure.old.builtins.property function in sure

# we are able to directly delete it from the object's __dict__.
                del self.__dict__[name]

        def setter(method, self, other):
            if isinstance(self, type):
                # if the attribute has to be set to a class object
                # we cannot use ``self.__dict__[name] = other`` directly because we cannot
                # modify a mappingproxy object. Thus, we have to set it in our
                # proxy __dict__.
                overwritten_object_handlers[(id(self), method.__name__)] = other
            else:
                # if the attribute has to be set to an instance object
                # we are able to directly set it in the object's __dict__.
                self.__dict__[name] = other

        return builtins.property(
            fget=method,
            fset=partial(setter, method),
            fdel=partial(deleter, method),
        )

def assertionproperty(func):
    return builtins.property(assertionmethod(func))

assert self.obj > num, msg
        return True

    @assertionmethod
    def length_of(self, num):
        if self.negative:
            return self._that.len_is_not(num)

        return self._that.len_is(num)

    def called_with(self, *args, **kw):
        self._callable_args = args
        self._callable_kw = kw
        return self

    called = builtins.property(called_with)

    @assertionmethod
    def throw(self, *args, **kw):
        _that = AssertionHelper(self.obj,
                     with_args=self._callable_args,
                     and_kwargs=self._callable_kw)

        if self.negative:
            msg = ("{0} called with args {1} and kwargs {2} should "
                   "not raise {3} but raised {4}")

            exc = args and args[0] or Exception
            try:
                self.obj(*self._callable_args, **self._callable_kw)
                return True
            except Exception as e: