How to select non-native artwork with script?

There was a post (which is now a ghost) about it. I believe Carlos Canto made this.

// select non-Native objects
// https://forums.adobe.com/thread/1886524


if (app.documents.length > 0 ) {
var idoc = app.activeDocument;
var NonNativeItemsCount = idoc.nonNativeItems.length;
if (NonNativeItemsCount>0) {
for (i=0; i<NonNativeItemsCount; i++) {
idoc.nonNativeItems[i].selected = true;
}
alert('there are ' + NonNativeItemsCount + ' non-Native items');
}
else
alert('there are no non-Native items');
}