gistfile1.txt

class Migration(SchemaMigration):

    def forwards(self, orm):
        
        # Adding field 'Publication.subclass'
        db.add_column('publishing_publication', 'subclass', self.gf('django.db.models.fields.CharField')(default='Publication', max_length=48), keep_default=False)
        for obj in orm.Publication.objects.all():
            obj.subclass = '{0}.{1}'.format(
                obj._meta.app_label, obj.__class__.__name__)
            obj.save()