Questions about the assessment for Django framework

I’m going through the Django framework assessment by myself and discovered that in the officially posted code, they created a rather complicated view to give all the blogs an author created. The class defined is here.

Why can’t I just write it as follows?

class AuthorDetailView(generic.DetailView):
      model = Author

and in the template

{% for post in author.post_set.all %}
  <li><b class="term"><a href="{{ post.get_absolute_url }}">{{ post.title }}</a>
({{ }})</b></li>
{% endfor %}

since in the model we’ve already defined in Meta that the sorting of the posts is based on date. In this way, I don’t need to overwrite get_queryset() and get_context_data().