pub fn change_output_property<'c, 'input, Conn>(
    conn: &'c Conn,
    output: Output,
    property: Atom,
    type_: Atom,
    format: u8,
    mode: PropMode,
    num_units: u32,
    data: &'input [u8]
) -> Result<VoidCookie<'c, Conn>, ConnectionError>
where Conn: RequestConnection + ?Sized,