def serialized(self):
        to_ret = {}
        for group, requirements in self.items():
            to_ret[group] = [str(requirement) for requirement in requirements]
        return to_ret
def update_snapshot(self, snapshot_id, **kwargs):
        """Updates a snapshot."""
        put_body = json.dumps({'snapshot': kwargs})
        resp, body = self.put('snapshots/%s' % snapshot_id, put_body)
        body = json.loads(body)
        return resp, body['snapshot']