BackboneJS-Model isNew

BackboneJS-Model isNew

<!DOCTYPE html>
   <head>
      <title> Model Example</title>
         <script src="https://code.jquery.com/jquery-2.1.3.min.js" type="text/javascript"></script>
         <script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.2/underscore-min.js" type="text/javascript"></script>
         <script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.1.2/backbone-min.js" type="text/javascript"></script>
         <script type="text/javascript">
            var Person = Backbone.Model.extend({
               defaults: {
                  title: 'CodingDict'
               }
            });
            var person = new Person();
            document.write(person.isNew());
         </script>
   </head>
   <body></body>
</html>