Python django.contrib.admin 模块，VERTICAL 实例源码

def formfield_for_choice_field(self, db_field, request=None, **kwargs):
        """
        Get a form Field for a database Field that has declared choices.
        """
        # If the field is named as a radio_field, use a RadioSelect
        if db_field.name == 'redirect_type':
            kwargs['widget'] = AdminRadioSelect(attrs={'class': get_ul_class(admin.VERTICAL)})
        return db_field.formfield(**kwargs)