Create a change calculator, where given an initial value it returns the change to receive. For instance, if you ask change for 50, it would give me back 2 bills of 10 and a bill of 10 (considering it has that values).
If you ask change for 15, it returns 3 bills of 5.
If you ask change for 17, it returns a bill of 10, a bill of 5 and a coin of 2.
If the change given back is not equal to the initial money, return an empty list.