def test_cleaning():
    lol = TestTemplateModel(another_template='admin/change_form.html')
    lol.full_clean(exclude=['empty_template', 'template'])
def test_cleaning_error():
    lol = TestTemplateModel(another_template='guess.json')
    with pytest.raises(ValidationError):
        lol.full_clean(exclude=['empty_template', 'template'])