This code not found

odoo.define('gencontratos.main_page',function(require){
    "use strict";

    var Widget = require('web.Widget');

    var RootPage = Widget.extend({
        template:'qwebRoot',

        start:function(){
            console.log(this.$el);

            console.log('start----------');
        }
    })

    var page = new RootPage();
    //page.setElement('#root');
    page.appendTo('#root');
    console.log('loaded---------------------');

But if I usé setInterval found

setInterval(función() {

page. appendTo("#root") ;

},5000)

If not usé ser interval show the error template not found