I use it like this:

    {% render_block "js" %}
    <script>
    (function($) {
      // CMS.$ will be passed for $
      $(document).ready(function () {
        var options = CMS.Modal.getOptions();
        options.has_django_suit = true;
        console.log(options);
        CMS.Modal.setOptions(options);
      });
    })(CMS.$);
    </script>