Modify the Inventory Program to include an add button,

Modify the Inventory Program to include an add button, a delete button, and a modify button on the GUI. These buttons should allow the user to perform the corresponding actions on the item name, the number of units in stock, and the price of each unit. An item added to the inventory should have an item number one more than the previous last item.



Add a save button to the GUI that saves the inventory to a C:\data\inventory.dat file.