As soon as posible, Please

Write a Python program that implements the following options based on the user choice: 1. Find Factorial of a number 2. Exchange Letter case in a String. 3. EXIT Implement the functions as follows: 1. find_fact: This function takes an integer number and returns the factorial of this number. 2. exchange_letter_case: This method takes a string and returns the string with exchanging lowercase letters with uppercase letters and vice versa in the string. 3. exit: This option will exit the program