I have a model with a self referential field called parent.
Model:

```
class Zone(BaseModel):
    name = models.CharField(max_length=200)
    parent = models.ForeignKey('self', models.CASCADE, blank=True, null=True, related_name='children')

    def __unicode__(self):
        return self.name

```

Serializer:

```
class ZoneSerializer(ModelSerializer):
    parent = PrimaryKeyRelatedField(many=False, queryset=Zone.objects.all())
    parent_disp = StringRelatedField(many=False, source="parent")

    class Meta:
        model = Zone
        fields = ('id', 'name', 'parent', 'parent_disp')

```

Now I want to serialize the parent of the zone and its parent and its parent till parent is none.
I found recursive serialization methods for children but not for parent.
How can I do this?