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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.