<p>There are 3 trees that offer dream services.</p>
<p>Which tree do you prefer to dream with?</p>
<p>Please choose one:</p>

<form method="POST" action="/generate">
    <input type="hidden" name="location" value="{{ location }}" />

    <ul>
        {% for tree in trees %}
        <li><input type="radio" name="tree" value="{{ loop.index0 }}"> {{ tree }}</li>
        {% endfor %}
    </ul>
    <input type="submit" value="Generate dreams"/>
</form>