Taking A vacation lesson was really  great for me.I have learnt a lot from it.It includes function and how it works.Function blocks begin with the key word def followed by the function name and parentheses.You can also define parameters inside these parentheses.In this lessons i created some functions that calculate everything that cost and how much you cost in vacation.It is really wonderful to know that how the function works in python.Also You can create your own function by following the same method.