def instance_url(self):
        object_id = self.get('object_id')
        if not object_id:
            raise error.InvalidRequestError(
                'Could not determine which URL to request: %s instance '
                'has invalid ID: %r' % (type(self).__name__, object_id), 'object_id')
        object_id = util.utf8(object_id)
        base = self.class_url()
        extn = urllib.quote_plus(object_id)
        return (base, extn) % "%s/%s"
dataset/ETHPy150Open goshippo/shippo-python-client/shippo/resource.py/APIResource.instance_url/swapped operands of `%`