{% load wagtailadmin_tags i18n %}
<legend>{{ self.verbose_name }}</legend>
<ul class="fields">
  <li>
    <div class="field">
      <label for="{{ self.children.0.id_for_label }}">{{ self.verbose_name }}</label>
      <div class="field-content">
        <div class="field-content">
          <ul class="fields">
            {% for child in self.children %}
              <li class="{{ child.classes|join:" " }}">
                {% if forloop.first %}
                  <label for="{{ child.id_for_label }}">{{ child.heading }}</label>
                {% endif %}
                {{ child.bound_field}}
              </li>
            {% endfor %}
            {% for child in self.children %}
              {% if child.bound_field|has_unrendered_errors %}
                <p class="error-message">
                  {% for error in child.bound_field.errors %}
                    <span>{{ error|escape }}</span>
                  {% endfor %}
                </p>
              {% endif %}
            {% endfor %}
          </ul>
        </div>
      </div>
    </div>
  </li>
</ul>