http://127.0.0.1:8000/boards/1/

python manage.py migrate

#boards/models.py

class Topic(models.Model):

    views = models.PositiveIntegerField(default=0) # <- here

python manage.py makemigrations

python manage.py migrate

#boards/views.py 

def topic_posts(request, pk, topic_pk):

    topic = get_object_or_404(Topic, board__pk=pk, pk=topic_pk)

    topic.views += 1

    topic.save()

    return render(request, 'topic_posts.html', {'topic': topic})

<!--templates/topics.html-->

{% for topic in topics %}

    <tr>

        <td><a href="{% url 'topic_posts' board.pk topic.pk %}">{{ topic.subject }}</a></td>

        <td>{{ topic.starter.username }}</td>

        <td>{{ topic.replies }}</td>

        <td>{{ topic.views }}</td> <!-- here -->

        <td>{{ topic.last_updated }}</td>

    </tr>

{% endfor %}