Goal: Learn to use mutators and accessors to change stateful objects.

Assignment: Assume the Locker class already exists. The class has an attribute called

code that stores the locker

passcode when it's locked. It also implements:

a method change$\_$code that allows to change said attribute, taking two string parameters, the first should equal the

current code, the second being the new code. If and only if the first parameter is equal to code, the code is

updated;

a method unlock that takes one parameter, unlocking the locker if the parameter equals the code.

Assume also the variable my$\_$locker refers to a Locker object. Write a statement that changes my$\_$locker's code from

$"2134"$ to $"1933",$ then unlocks the locker.