code: def get_shipping_cost(settings, country_code=None, name=None):
      
      shipping_rate = None
      if settings.default_shipping_enabled:
          shipping_rate = {
              "rate": settings.default_shipping_rate,
              "description": "Standard shipping to rest of world",
              "carrier": settings.default_shipping_carrier
          }
      elif not country_code:
          raise InvalidShippingCountry
  
      if country_code:
          qrs = models.ShippingRate.objects.filter(countries__in=[country_code], name=name)
          count = qrs.count()
          if count == 1:
              shipping_rate_qrs = qrs[0]
          else:
              raise InvalidShippingRate()
          shipping_rate = {
              "rate": shipping_rate_qrs.rate,
              "description": shipping_rate_qrs.description,
              "carrier": shipping_rate_qrs.carrier}
      return shipping_rate
docs: Return the shipping cost for a given country code and shipping option (shipping rate name)