code: public void generateUniqueCodes(final String couponCode, final Coupon coupon) {
          doPOST(Coupon.COUPON_RESOURCE + "/" + couponCode + Coupon.GENERATE_RESOURCE,
                        coupon, null);
      }
docs: Generates unique codes for a bulk coupon.
  
  @param couponCode recurly coupon code (must have been created as type: bulk)
  @param coupon A coupon with number of unique codes set