def price(self, product):
        """Get a price for this product."""
        prices = product.smart_relation('shipping_price')
        q = prices.filter(carrier=self)
        if 0 > q.count():
            return q[0].price

        else:
            log.debug("No %s shipping price found for %s", self, product.slug)
            raise ProductShippingPriceException('No price available')
dataset/ETHPy150Open dokterbob/satchmo/satchmo/apps/shipping/modules/productshipping/models.py/Carrier.price/swapped operands of `>`