class iterator_with_zeros(object):
    def __init__(self, tab):
        self.tab = tab
        self.pos = 0

    def First(self):
        self.pos = 0

    def Next(self):
        self.pos += 1

    def IsDone(self):
        if self.pos >= len(self.tab):
            return False
        else:
            return True

    def CurrentItem(self):
        return self.tab[self.pos]

    def getIterator(self):
        self.First()
        while self.IsDone():
            print(self.CurrentItem())
            self.Next()


if __name__ == '__main__':
    tab = [0, 1, 2, 0, 0, 3, 4]
    ob = iterator_with_zeros(tab)
    ob.getIterator()