code: func (ps *PaperSize) GetPPDName() (string, error) {
  	c := C.gtk_paper_size_get_ppd_name(ps.native())
  	if c == nil {
  		return "", nilPtrErr
  	}
  	return C.GoString((*C.char)(c)), nil
  }
docs: // GetPPDName() is a wrapper around gtk_paper_size_get_ppd_name().