PROBLEM 1: CHECKING FOR PASSWORD VALIDITY (a) Write a function isValidPassword that checks the validity of passwords. The function takes a string (i.e., a password) and returns a boolean value (i.e., True if the password is valid and False if the password is invalid). A password is valid if the followings hold: - Has at least 1 letter between [a-z] and 1 letter between [A-Z] Has at least 1 number between [0-9 -Has at least 1 character from [$#] - Has minimum length 6 characters - Has maximum length 16 characters - Starts with an uppercase letter - Ends with a digit (b) Test the above function by writing a program that ask the user to enter a password, and print on the screen whether or not it is valid. The program asks the user to enter another password if the previous entry was invalid. However, after three unsuccessful trials the program locks the user out by printing an appropriate message and exiting. Date: Problem 2: Adapted from Opencourseware