An interactive fiction by Juhana Leinonen (2008) - the Inform 7 source text
The keyhole is a part of the celldoor. It is by the door. The description is "There's a tiny keyhole in the cell door[if the cell is dark] where from a faint beam of light enters the cell[end if]. Too bad you don't have the key."
Understand "lock" and "key hole" as the keyhole.
Instead of looking under the keyhole:
say "There's nothing under it but the door."
Instead of looking through the keyhole:
if the guard is in the cell:
say "You can't see anything through the keyhole. The guard's in the way.";
say "Through the keyhole you see a small part of the corridor behind the door. Sweet freedom!";
Instead of locking the keyhole with:
say "The idea would be to [italic type]unlock[roman type] it.".
Instead of unlocking the keyhole with:
say "That's not something that you could use to pick the lock. Not that you knew how even with a real set of lockpicks."
Understand "pick [keyhole] with [something]" as unlocking it with.