Is this one of the places where I had accidentally left in code that passed "Oz" as a parameter to FiniteStateWizard? (I mentioned that in an email, and I thought I had posted a fixed version of the file on Moodle, but maybe not.)
If so, just remove the comma and the "Oz" from the Wizard constructor.
Side note: the "self" parameter is kind of like the "this" in Java -- but in Python, you have declare it as the first formal parameter in each method of a class, even though you don't pass it in as an actual parameter when you call that method. This explains some of how Python counts the #s of parameters (3 vs. 4).