Twig for loop for arrays with keys

There's this example in the SensioLab page on the for tag:

<h1>Members</h1>
<ul>
    {% for key, user in users %}
        <li>{{ key }}: {{ user.username|e }}</li>
    {% endfor %}
</ul>

http://twig.sensiolabs.org/doc/tags/for.html#iterating-over-keys

I found the answer :

{% for key,value in array_path %}
    Key : {{ key }}
    Value : {{ value }}
{% endfor %}