def test_render_none(self):
        self.check_html(self.widget(choices=self.beatles), 'beatles', None, html=(
            """<select multiple="multiple" name="beatles">
            <option value="J">John</option>
            <option value="P">Paul</option>
            <option value="G">George</option>
            <option value="R">Ringo</option>
            </select>"""
        ))
If the value is None, none of the options are selected.
dataset/ETHPy150Open django/django/tests/forms_tests/widget_tests/test_selectmultiple.py/SelectMultipleTest.test_render_none