    def test_siblings_cant_talk_parent(self):
        # ensure 'unidirectional' attribute is respected for contexts started
        # by children.
        self.router.unidirectional = True
        parent = self.router.local()
        parent.call(test_siblings_cant_talk_remote)
Software security is not security software. Here we're concerned with topics like authentication, access control, confidentiality, cryptography, and privilege management.