title: Ipython Iframe cannot find reference local js file under jupyter notebook
body: <p>When I use Ipython.Iframe package under jupyter notebook, my HTML file render fail.
  And the errror is <strong>Uncaught ReferenceError: echarts is not defined</strong></p>
  <p>But If I just open my html file on the web browser, it shows normally.</p>
  <p>The js import approach is like</p>
  <p>'script src=&quot;echarts.min.js&quot;&gt;&lt;/script</p>
  <p>Does anyone know how to solve this?
  Thanks</p>