You treat the snake by removing the mites and treating the cage. There are some direct "spray-on" mite killers that you can buy from pet stores or online sellers, but most people don't trust them a bit. You'd be better off giving her a bath, just with water - generally the mites fall off.

The mites appear from an outside source like substrate or branches. If it turns out that you do have mites, you'll also want to replace your bedding and use paper towels until the mites have cleared up. This way it's not as easy for them to reproduce or hide from you.

Good luck. Glad to see someone so concerned and inquisitive about their pet.