Oh, I see. So it's like she's just holding it open? If you got her recently from Petsmart/Petco, it's possible that you bought a sick snake. They don't tend to have the best care of them there.

Keep watching for signs of RI or other issue and let us know. If you can get a picture of her doing it (or find a picture that looks like it) then that might help.

Hope she's okay.