'Get a form Field for a database Field that has declared choices.'

def formfield_for_choice_field(self, db_field, request=None, **kwargs):

    if (db_field.name in self.radio_fields):
        if ('widget' not in kwargs):
            kwargs['widget'] = widgets.AdminRadioSelect(attrs={'class': get_ul_class(self.radio_fields[db_field.name])})
        if ('choices' not in kwargs):
            kwargs['choices'] = db_field.get_choices(include_blank=db_field.blank, blank_choice=[('', _('None'))])
    return db_field.formfield(**kwargs)
