gtk/print.go
func (ps *PrintSettings) SetSefaultSource(defaultSource string) {
	cstr := C.CString(defaultSource)
	defer C.free(unsafe.Pointer(cstr))
	C.gtk_print_settings_set_default_source(ps.native(), (*C.gchar)(cstr))
}
func (ps *PrintSettings) SetSefaultSource(defaultSource string) {
	cstr := C.CString(defaultSource)
	defer C.free(unsafe.Pointer(cstr))
	C.gtk_print_settings_set_default_source(ps.native(), (*C.gchar)(cstr))
}
// SetSefaultSource() is a wrapper around gtk_print_settings_set_default_source().