def instance_url(self):
        token = util.utf8(self.id)
        customer = util.utf8(self.customer)

        base = Customer.class_url()
        cust_extn = urllib.quote_plus(customer)
        extn = urllib.quote_plus(token)

        return (base, cust_extn, extn) % "%s/%s/subscriptions/%s"
dataset/ETHPy150Open stripe/stripe-python/stripe/resource.py/Subscription.instance_url/swapped operands of `%`