<p>
<form id="search_form" method="post" action="{{ url }}">
{% for field in search_form %}
    {% if field.errors %}<fieldset>{% endif %}
    {{ field }}
    {% if field.errors %}<p class="search_form_errors">{{ field.errors }}</p>{% endif %}
    <input type="submit" name="search plugin" value="search" />
    {% if field.errors %}</fieldset>{% endif %}
{% endfor %}
</form>
</p>