Write a program that runs like a cashier in a store. The program should use a while loop and prompt for the quantity and unit price of each item being purchased. The number of different items cannot be known in advance so the loop should continue until zero is entered for the quantity. A subtotal should be printed after each item's data has been rung up. See Sample Output. When the loop ends the program should report the number of different items purchased and the total amount due. Sample Output

Python