This musical number feels natural in that it’s performed by students in a show choir, rehearsing on a stage. It’s an example of how description of a song or musical sequence can be sparse, but also get the point of across. This is a great moment to look at if you’re hoping to casually describe a song moment in your script, but don’t necessarily want to include the lyrics. 

But if you do include lyrics, note that here they’re italicized and in quotes.