Provide Embedded Demo Sound Files for People to Select (& Automatically Upload) Inside Web App


I have a Streamlit app in which end-users can upload sound files onto my web app. I want people to be able to use / test out my web app even when they don’t have sound files available on their local machines to directly upload.

As such, I was hoping to include (on the left sidebar) 3 different mp3 demo files. The end user selects one of them and it gets automatically uploaded in. Subsequently, my code ingests the audio file and then does stuff to it (already programmed).

I saw a sample streamlit app that did just this. But I can’ find it anymore. Does anyone have suggestions / document links to achieve this functionality? Or sample streamlit app where I can see its code?