fib.py

def fibsy(n, i, g, s):
    if n > 0 and g == 0:
        n -= 1
        print 0
        return fibsy(n, i, 1, s)
    elif n > 0 and s == True:
        n -= 1
        print 1
        return fibsy(n, 1, g, False)
    elif n > 0:
        n -= 1
        print g
        i, g = g, i + g
        return fibsy(n, i, g, s)
    else:
        print "Finished."
        return None


def fib(n):
    return fibsy(n, 0, 0, True)


if __name__ == '__main__':
    print fib(10)