code: def proprietry_discount_code_for_rrp=(code)
        price    = price_get(2)
        if price.nil?
          self.rrp_inc_sales_tax = 0
          price    = price_get(2)
        end
  
        discount = price.discounts_coded.find { |disc| disc.discount_code_type == 2 }
  
        if discount.nil?
          discount = ONIX::DiscountCoded.new
          discount.discount_code_type = 2
          price.discounts_coded << discount
        end
        discount.discount_code = code
      end
docs: set the discount code that describes the rrp in this file