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<ul id="list1"></ul>
<hr />
<button id="btn1">+ Add new item</button>





                // This the initial state of the app
const todos = [
  'buy milk',
  'clean kitchen',
  'learn js',

// This helper function will "render" a new
// DOM item into an HTML list
const appendItem = (item) => {
  const el = document.createElement('li')
  const elText = document.createTextNode(item)

// Here you need to clear the list from its
// content, so that you can later re-render all
// the content.
const clearList = () => {
  // ?? Can you find a better way to do this ??
  document.getElementById('list1').innerHTML = ""

// This is the main rendering logic, it is
// often a simple 2 steps operation:
// 1. cleanup
// 2. re-create everything
const renderList = () => {

Do you remember how to associate an action
to a button? We did it a few steps ago.

// As soon the app starts, we run the first
// rendering so to show the initial state.