def unregister(self, message, toURL, contact):
        try:
            expires = int(message.headers["expires"][0])
        except __HOLE__:
            self.deliverResponse(self.responseFromRequest(400, message))
        else:
            if expires == 0:
                if contact == "*":
                    contactURL = "*"
                else:
                    name, contactURL, params = parseAddress(contact)
                d = self.registry.unregisterAddress(message.uri, toURL, contactURL)
                d.addCallback(self._cbUnregister, message
                    ).addErrback(self._ebUnregister, message
                    )
dataset/ETHPy150Open nlloyd/SubliminalCollaborator/libs/twisted/protocols/sip.py/RegisterProxy.unregister