class Topic(models.Model):
    """A topic the user is learning about."""
    text = models.CharField(max_length=200)
    date_added = models.DateTimeField(auto_now_add=True)
    owner = models.ForeignKey(User)

    def __str__(self):
        """Return a string representation of the model."""
        return self.text

In [21]: Topic.objects.create(text='Celery', owner_id=1)
Out[21]: <Topic: Celery>
In [34]: celery = Topic.objects.get(pk=22)
In [35]: isinstance(celery, Topic)
Out[35]: True