{% if tableHeaderRows is not empty %}
    <thead>
    {% for tableHeaderRow in tableHeaderRows %}
        <tr>
            {% for column in tableHeaderRow.columns %}
                <th{% if column.colspan > 1 %} colspan="{{ column.colspan }}"{% endif %}>
                    {%- for child in column.children -%}
                        {{- renderNode(child) -}}
                    {% endfor %}</th>
            {% endfor %}
        </tr>
    {% endfor %}
    </thead>
{% endif %}