JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.2.3/backbone-min.js"></script>
<div id="result">
</div>

JavaScript

var collection = new Backbone.Collection([
	{ id: 'undefined', name: 'Undefined model'},
  { id: '1', name: 'Defined one'}
]);

document.getElementById('result').textContent = collection.get('1').get('name');