def get_vae(self):
        if hasattr(self, 'vae'):
            return self.vae
        else:
            return None
Return 403 if user does not have permissions to preview a scribble_field.
dataset/ETHPy150Open lisa-lab/pylearn2/pylearn2/models/vae/conditional.py/Conditional.get_vae--crossover with--dataset/ETHPy150Open caktus/django-scribbler/scribbler/tests/test_views.py/PreviewTestCase.test_permission_required_scribble_field