Python 23 Generator

gistfile1.py

class Prime23(object):
    step = 0
    prime = 1
    cases = {
       1 : 2,
       2 : 3,
       3 : 5
    }

    @classmethod
    def __iter__(self):
        return self
    
    @classmethod
    def next(self):
        if (self.step != 0):
            self.prime += self.step
            self.step = 6 - self.step
        else:
            self.prime = self.cases[self.prime]
            if (self.prime == 5):
                self.step = 2
        return self.prime