What is the shipment duration for order number CA-2011-134103?
shipment duration = subtract("Ship Date", "Order Date"); order number CA-2011-134103 refers to "Order ID" = 'CA-2011-134103'
SELECT DISTINCT strftime('%J', `Ship Date`) - strftime('%J', `Order Date`) AS duration FROM central_superstore WHERE `Order ID` = 'CA-2011-134103'