UNB/ CS/ David Bremner/ teaching/ cs2613/ books/ diveintopython3/ examples/ fibonacci2.py
'''Fibonacci iterator'''

class Fib:
    '''iterator that yields numbers in the Fibonacci sequence'''

    def __init__(self, max):
        self.max = max

    def __iter__(self):
        self.a = 0
        self.b = 1
        return self

    def __next__(self):
        fib = self.a
        if fib > self.max:
            raise StopIteration
        self.a, self.b = self.b, self.a + self.b
        return fib

# Copyright (c) 2009, Mark Pilgrim, All rights reserved.
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