How do I... Embed image depending on the description?

Good for when you just want to change a user's profile image without changing the markup/code.
You just use the image's description for filtering.

{{
var photoList = map.select(page.files, "string.contains($.value.description, 'photo')");
if (#photoList > 0) {
  var photoFile = map.values(photoList)[0];
  web.image(photoFile.uri, 187, 187, photoFile.description);
 }
else {
  web.html("no photo");
 }
}}