pub unsafe extern "C" fn pdf_signature_appearance_signed(
    ctx: *mut fz_context,
    rect: fz_rect,
    lang: fz_text_language,
    img: *mut fz_image,
    left_text: *const c_char,
    right_text: *const c_char,
    include_logo: c_int
) -> *mut fz_display_list