How to list documents from table grouped by id? - postgresql

Question

I'm making a template to show documents by its parts (title, annotation, contenttext).
{% block header %}
<h1>{% block title %}Documents{% endblock %}</h1>
{% endblock %}
{% block content %}
{% for document in documents | groupby('documentid' %}
<div class="card mb-3">
<div class="card-header">
{{ document.annotation }}
<span class="badge badge-pill badge-primary">{{ document.title}}</span>
</div>
<div class="card-body">
<p class="card-text">{{ document.contenttext }}</p>
</div>
</div>
{% endfor %}
{% endblock %}
The table looks like that:
documentid title annotation contenttext
1 abc abc abc
1 abc abc def
2 zzz xxx yyy
3 ooo mmm fff
Two first rows have the same documentid so i want to display both 'abc' and 'def' in the same document. And then go frther.
Which construction will allow me to do that?
title|annotation|contenttext
doc1: abc | abc | abc def
doc2: zzz | xxx | yyy
doc3: ooo | mmm | fff