Why Can't I Use a List Variable with Django's 'with' Template Tag?

I'm trying to assign a list to a variable using Django's {% with %} template tag, like this:

DJANGOCopied
{% with items=['item1', 'item2', 'item3'] %}
<ul>
    {% for item in items %}
        <li>{{ item }}</li>
    {% endfor %}
</ul>
{% endwith %}

Django doesn't seem to parse this syntax. Is there a specific reason why lists cannot be assigned this way, or is there an alternative syntax to accomplish this?