Hi Sebastian, definitely confusing that the behavior is different and this took me a while to figure out. Your calls are incorrect and I was more puzzled why the first was working than why the second was not.
The ExitPolicy class takes a list of rules. For example...
ExitPolicy('reject *:80', 'accept *:*')
Your comma is within the quotes. If you moved it out of the quotes it would work as intended...
Didn't intend that but it works due to how ExitPolicy handles arguments internally and I'm cool with that. It's an intuitive way to use the class. It only balked on you due to ending the string with a comma.
Pushed a little tweak so the commands you gave now work.