def clean_semver(cls, version_spec):
        return re.sub(r"([<>=~])\s+?v?", "\\1", version_spec, re.IGNORECASE)
def object_id(self):
        return ("ip-path-mtu-%d-%s-%d" % (self.table_id,
                                          self.nh,
                                          self.pmtu))