jstree contextmenu enable/disable node

HTML

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/jstree/3.2.1/themes/default/style.min.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/jstree/3.2.1/jstree.min.js"></script>
<div id="anuj">
  <ul>
      <li>Root node 1
        <ul>
          <li id="child_node_1">Child node 1</li>
          <li>Child node 2</li>
        </ul>
      </li>
      <li>Root node 2</li>
    </ul>
</div>

JavaScript

$( function() {
	$( "#anuj" ).jstree( {
   	plugins: [ "contextmenu" ],
    "contextmenu": {
			"items": function( $node ) {
				return {
					"Enable": {
						"label": "Enable",
						"action": function( obj ) {
            	$( "#anuj" ).jstree( "enable_node", $node );
						}
					},
          "Disable": {
						"label": "Disable",
						"action": function( obj ) {
            	$( "#anuj" ).jstree( "disable_node", $node );
						}
					}
				};
			}
		}
	} ).on( "ready.jstree", function( e, data ) {
  	data.instance.open_all();
	} );
  $( "#anuj" ).jstree( "disable_node", "child_node_1" );
} );