django-localized-fields/localized_fields/templates/localized_fields/multiwidget.html

{% with widget_id=widget.attrs.id %}
<div class="localized-fields-widget" role="tabs" data-synctabs="translation">
    <ul class="localized-fields-widget tabs">
    {% for widget in widget.subwidgets %}
        <li class="localized-fields-widget tab">
            <label for="{{ widget_id }}_{{ widget.lang_code }}">{{ widget.lang_name|capfirst }}</label>
        </li>
    {% endfor %}
    </ul>
    {% for widget in widget.subwidgets %}
        <div role="tabpanel" id="{{ widget_id }}_{{ widget.lang_code }}">
            {% include widget.template_name %}
        </div>
    {% endfor %}
</div>
{% endwith %}