<table>
    <tr>
        <th>Worker</th>
        <th>Key count</th>
        <th>Key list</th>
    </tr>

    {% for worker, keys in has_what.items() %}
    <tr>
        <td>{{ worker }}</td>
        <td>{{ keys | length }}</td>
        <td>
            <details>
            <summary style='display:list-item'>Expand</summary>
            <table>
            {% for key in keys %}
                <tr><td>{{ key }}</td></tr>
            {% endfor %}
            </table>
            </details>
        </td>
    </tr>
    {% endfor %}
</table>