Sorty McSortSort

Write a function that takes two parameters, an array of user objects and a boolean 'sortAscending'. If the boolean 'sortAscending' is true, sort the array of user object by last name from A-Z. If the boolean is false, sort the array from Z-A.

Try to do this without using Array.sort().

var users = [
    {
        firstName: "Billy",
        lastName: "Madison", 
        age: 32
    },
    {
        firstName: "Tommy",
        lastName: "Pickles", 
        age: 32
    },
    {
        firstName: "Ray",
        lastName: "Charles", 
        age: 32
    },
    {
        firstName: "Lady",
        lastName: "Gaga", 
        age: 32
    },
    {
        firstName: "Elizabeth",
        lastName: "Taylor", 
        age: 32
    },
    {
        firstName: "Led",
        lastName: "Zeplin", 
        age: 32
    },
    {
        firstName: "Micael",
        lastName: "Johnson", 
        age: 32
    },
    {
        firstName: "Keri",
        lastName: "Strug", 
        age: 32
    },
    {
        firstName: "Chucky",
        lastName: "Finster", 
        age: 32
    },
    {
        firstName: "Angelica",
        lastName: "Pickles", 
        age: 32
    },
]