#-----------which Python will treat as comments and ignore. Please put your definition of the needed function between these two lines. And remember, you can define a function that takes advantage of Python's built-in functions and methods, unless the instructions in the program comments recommend against this. Also, you can write more than one function to solve a problem. For example, if the needed function is F(x), you could define G(a,b) and then in the definition of F, you could call (a,b) in an expression inside the body of F.