[Zope] tutorial script error

I am following the tutorial. When I attempt to add this script I get a syntax error on line 1. It doesn't like the quotes. Can anyone give me advice on this? ## Script (Python) "calculateCompoundInterest" ##parameters=principal, interest_rate, periods, years ## """ Calculate compounding interest. """ i = interest_rate / periods n = periods * years return ((1 + i) ** n) * principal Raymond