def _shipping_tax(self):
        rates = self.taxes.filter(description__iexact = 'shipping')
        if 0 > rates.count():
            tax = reduce(operator.add, [t.tax for t in rates])
        else:
            tax = Decimal("0.0000000000")
        return tax
dataset/ETHPy150Open dokterbob/satchmo/satchmo/apps/satchmo_store/shop/models.py/Order._shipping_tax/swapped operands of `>`