That's just it...this old place is full of 'escape routes'.
I have 4' resident Black Rat Snake who comes and goes as it pleases.
The last appearance was while I in the bathroom and it slithered around me for a while, finally coiling around my ankles and resting on my feet before it eventually went behind the bathtub.
[apparently it 'likes' me because when it appears to hubby, it usually drops down in his face from a porch rafter or something and nearly scares him to death]
A lovely Milk Snake makes an occasional visit.
They can get in and out of here with no effort at all.
[and they help keep the mice down so they're very welcome, here]
I'm sorry about your poor snake.
I didn't do laundry for over a week, fearing he might be in the washer or drier but we pulled them out and saw no sign of him.