Django templates problem — {% if object|length > 4 %} raises TemplateDoesNotExist: 500.html

Question

I have the following in my template.

{% block content %}
    {% for album in albumsList %}
        {% if fotosList %}
            <div class="photoalbum-wrapper">
                <h3>{{ album.title }}</h3>
                <ul class="photoalbum">
                    {% for foto in fotosList %}<li>item</li>{% endfor %}
                </ul>
                {% if fotosList|length > 4 %}
                    <a href="#" class="trigger">больше <span>&#9660;</span></a>
                {% endif %}
            </div>
        {% endif %}  
    {% endfor %}
{% endblock %}

And it raises TemplateDoesNotExist: 500.html.

If i write simple {{ fotoList|length }} it works okay.

Answer 1

This is a very old question. Since then, newer versions of Django support operators in if-statement out of the box, so the following code will work just fine:

{% if fotosList|length > 4 %}

{% endif %}