What is the padlock used for?

[Linux.Blue]

you can trap them in the steam chambers, but you don't need no padlock. If you really want to know how to get them in the steam chambers -

Spoiler below!

Lure them in with beef jerky. Once they get inside and start eating it, close the door and start steaming them. I'd go with closing the door, even though it seems like they can't get out, being steamed so often that they can't move well. but one time, I came across a dog who did manage to leave the steam chamber.