from threading import Thread


    def blocking_function(arg):
        ....


    pool = []
    for arg in args[:16]:
        f = lambda: blocking_function(arg)
        thread = Thread(target=f)
        thread.start()
        pool.append(thread)

It doesn't have true CPU parallelism like multiple processes would have, but it works for IO code.

It's a little gold nuggest in the multiprocessing lib.