Thanks again.
One more thing(sorry!):
"Notice what happens when you type "use defibrillator on bob" a second time - you get the same response again. You should know how to fix this now - update your "use defibrillator on bob" script to check for the "alive" flag. Update this now."
I actually don't know how to fix this, the tutorial didn't tell me like it seems to think it did. :/