def __init__(self, size_or_pool=1000):
        if isinstance(size_or_pool, GreenPool):
            self.pool = size_or_pool
        else:
            self.pool = GreenPool(size_or_pool)
        self.waiters = queue.LightQueue()
        self.used = False
        self.counter = 0
:param size_or_pool: either an existing GreenPool object, or the size a new one to create
dataset/ETHPy150Open veegee/guv/guv/greenpool.py/GreenPile.__init__