How to make the movie file in import folder in touchdesigner will always be the latest one?

Hello, I’m recently working on a project and have encountered a very distressing problem.
I combined the tutorials of this teacher QR Code Photobooth in TouchDesigner - Tutorial - YouTube
I created a photo booth, but now I really want the latest saved photos to be shown in the movie file when people take photos, so that everyone can see them.
I first tried importing the whole album with folder and then using op(‘folder3’)[‘1’,‘1’]
This code is put into the file, but it doesn’t produce changes, and I have to manually change the number in [] to switch between images.
I would appreciate if someone could give me some ideas.