pub fn change_device_key_mapping<'c, 'input, Conn>(
    conn: &'c Conn,
    device_id: u8,
    first_keycode: KeyCode,
    keysyms_per_keycode: u8,
    keycode_count: u8,
    keysyms: &'input [Keysym]
) -> Result<VoidCookie<'c, Conn>, ConnectionError>
where Conn: RequestConnection + ?Sized,