Update an existing person
        :param person: is the updated person that the client wants to update

def update_person(self, person):
        """
        Update an existing person
        :param person: is the updated person that the client wants to update
        """
        self._validate_regid(person.person_id)
        self._validate_subscriber_id(person.surrogate_id)

        for attr in MANAGED_ATTRIBUTES:
            person.attributes.pop(attr, None)

        url = "/notification/v1/person/{}".format(person.person_id)
        response = NWS_DAO().putURL(
            url, self._write_headers(), self._json_body(person.json_data()))

        if response.status != 204:
            raise DataFailureException(url, response.status, response.data)

        return response.status