Python-сообщество

def fib():
    a, b = 0, 1
    while True:
        yield a + b
        a, b = b, a + b

def two_streams(gen_func):
    def in_one(gen):
        a = 1
        for i in gen:
            if a % 2:
                yield i
                a = 0
            else:
                a = 1

    new = gen_func()
    new.next()
    return in_one(gen_func()), in_one(new)

def join_streams(*gens):
    while True:
        yield map(lambda x: x.next(), gens)

def take(gen, number):
    for i, g in enumerate(gen):
        if i <= number:
            yield g
        else:
            raise StopIteration


In [35]: for i in take(join_streams(*two_streams(fib)), 10):
   ....:     print i
   ....: 
[1, 2]
[3, 5]
[8, 13]
[21, 34]
[55, 89]
[144, 233]
[377, 610]
[987, 1597]
[2584, 4181]
[6765, 10946]
[17711, 28657]