Module not defined error

Hello guys i have created a custom app(frappe_light) and custom desk page am getting the following error whenever i load my desk page. Any help will be much appreciated @rmehta

 ReferenceError: frappe_light is not defined
    at Object.frappe.get_custom_menu (<anonymous>:71:16)
    at (<anonymous>:15:17)
    at get_sidebar_html (<anonymous>:27:33)
    at (<anonymous>:37:20)
    at Class.trigger_page_event (desk.min.js?ver=1565856989.0:9780)
    at Class.init (desk.min.js?ver=1565856989.0:9769)
    at new Class (desk.min.js?ver=1565856989.0:37)
    at desk.min.js?ver=1565856989.0:9736
    at Object.callback (desk.min.js?ver=1565856989.0:9721)
    at Object.callback [as success_callback] (desk.min.js?ver=1565856989.0:1437)
(anonymous) @ desk.min.js?ver=1565856989.0:1566

Here is my code

frappe.get_custom_menu = function(doctype) {{
         args: {
            doctype:"Menu Items",     
            fields: [ "item_label","item_type", "item_link"],
            //parent: ["Custom Menu"],
      callback: function(r) {
        //var a=r.message[0]