Get first item of QuerySet in template

Since Django 1.6 you can do

<img src="{{ entry.image_set.first.get_absolute_url }}">

You also can do: entry.image_set.all.0 in your template.

Not any shorter, but you could use first:

{% with entry.image_set.all|first as image %}
  <img src="{{ image.get_absolute_url }}">
{% endwith %}