How to use the @jupyter-widgets/controls.BoxModel function in @jupyter-widgets/controls

base.js
=================
JavaScript "frontend" complement of exatomic"s Universe
for use within the Jupyter notebook interface.
*/

"use strict";
var widgets = require("@jupyter-widgets/base")
var control = require("@jupyter-widgets/controls")
var three = require("./appthree")
var utils = require("./utils")
var semver = "^" + require("../package.json").version
console.log(`exatomic JS version: ${semver}`)


export class ExatomicBoxModel extends control.BoxModel {

    defaults() {
        return {
            ...super.defaults(),
            _model_name: "ExatomicBoxModel",
            _view_name: "ExatomicBoxView",
            _model_module_version: semver,
            _view_module_version: semver,
            _model_module: "exatomic",
            _view_module: "exatomic",
            linked: false
        }
    }

}