def f(x):
        # The parameter defines f()'s x.
        # Now define f()'s total.
        total = 99
        
        # Now try referring to some variables.
        # "x" refers to the f()'s x (which is 11) not main's x (which is 4)
        # f() doesn't have a y, so "y" refers to main's y (which is 6)
        total = x + y
        return (total) ** 3

if __name__ == "__main__":
        # Define main's x and main's y.
        x = 4 
        y = 6
        
        z = f(11)
        
        # There is no total defined here in main.
        print total