recursive jinja template

{% macro show_node(node) %}
   {% for key, value in node.__dict__.items() %}
        <span>{{key}}: </span>
        {% if True %} <-- not sure what to do here
            <span>Value: {{value}}</span>
        {%else%}
            {{ show_node(value) }}
        {% endif %}
   {% endfor %}
{% endmacro %}