CSV Product Create and Sort

We have a csv file with approx 48k products. In reality there are only approx 1600 unique products due to colour and size combinations. I need the group product created, with size in a field, with sizes available on that product listed in the field separated by |, and the same with the colour field. So we are basically condensing the 48k porducts into approx 1600 products as the size and colour combinations will be listed in 2 separate fields in the group product. example Product Name Colour Size SS6BROWN10 T-Shirt Brown 10 SS6BROWN12 T-Shirt Brown 12 SS6BROWN14 T-Shirt Brown 14 SS6BROWN16 T-Shirt Brown 16 SS6BLUE16 T-Shirt Blue 16 SS6WHITE16 T-Shirt White 16 what I would expect created SS6 T-Shirt Brown|Blue|White 10|12|14|16 If you need clarification please ask before bidding on this project.