what does localstorage setitem return code example

Example 1: how to setItem and getItem in javascript in localStorage

function set(){
    var sendJSON = JSON.stringify(allMovie);
    localStorage.setItem('allMovie',sendJSON)
}

function get(){
    var getJSON = localStorage.getItem('allMovie');
    if (getJSON){
        allMovie = JSON.parse(getJSON)
    }

}

Example 2: set localstorage

function set(){
    var sendJson = JSON.stringify(arrayName);
    localStorage.setItem('key',sendJson)
}