(python) Write a program with a user-defined function called 'clamp', which takes as an input a single integer. If the input number is negative, have the function return zero. If the value is postivie and greater than 255, have the function return 255. If the value is between 0 and 255, have the function return the number unaltered. Write a main program section that prompts the user to enter a number, recasts it to an integer, and calls the clamp function. The program should then print out the value returned by the function call..