data = Data.objects.all().order_by('date_ready'){% regroup data by date_ready as data_by_date %}
<ul>
{% for data in data_by_date %}
<li>{{ data.grouper }}
<ul>
{% for item in data.list %}
<li>{{ item.subject }} {{ item.body }}</li>
{% endfor %}
</ul>
</li>
{% endfor %}
</ul>