^C doesn't kill libconvert.py #25
Description
When you run libconvert.py, and try to stop it using ^C, it keeps running. It should stop. This is really bad when processing many submissions.
I think the problem is that each time you press ^C you are killing the current shell process, which returns control to python, and then python goes on to the next command.
Command or Assignment needs to check the exit value of the shell processes to see if an error has occurred. If an error has occurred it should probably raise an exception.