That is not a brilliant idea
For many reasons, the first and foremost being it isn't safe, a snake doesn't necessarily "pass through" a string and/or larger obstruction.
Secondly although it sounds in theory as if it would work, your snake isn't large enough for you to hear it feed. Thereby meaning you could be asleep, or in the shower etc.
I have a friend who lost their snake when it ate a washcloth that her rats had used in the cage. The snake escaped hit the laundry room, and ate the washcloth, it never survived the surgery to remove it. I dont remeber if it was her red tail or her green tree boa, both I do remember it was an adult.

Please reconsider that idea.