I want to sell a matching set of 2 prints on Etsy, I’m only going to offer these in sizes A0, A1, A2, A3, A4 and A5. My one question is, how do I set this up on Etsy so I can have 2 separate SKUs so when someone orders the set of two prints, PrintShrimp know it’s an order for 2 prints and which ones? Or is there a way of setting up an SKU on print shrimp with 2 prints attached to it??