Closure demo in Python

class make_fibonacci(object):
    def __init__(self):
        self.current = 0
        self._next = 1

    def __call__(self):
        fib = self.current
        self.current, self._next = self._next, self.current + self._next
        return fib

iterator = make_fibonacci()

for i in range(10):
    num = iterator()
    print num