Shuffle the output of an iterator

shuffle_with_pool.py

from typing import *
import random

def shuffle_iterable(i: Iterable, pool_size: int = 1024) -> Iterable:
    import random
    i = iter(i)
    pool = []

    # fill up the pool
    for item in i:
        pool.append(item)
        if len(pool) >= pool_size:
            break

    # play in it
    while len(pool) > 0:
        index = random.randrange(len(pool))
        yield pool[index]
        try:
            pool[index] = next(i)
        except StopIteration:
            del pool[index]
            break

    # drain it
    random.shuffle(pool)
    yield from pool