Get multiple items from a Queue.

        Gets at least one (blocking) and at most ``max_batch_size`` items
        (non-blocking) from a given Queue. Does not mark the items as done.

        :rtype: Sequence
        :returns: A sequence of items retrieved from the queue.

def _get_items(self):
        """Get multiple items from a Queue.

        Gets at least one (blocking) and at most ``max_batch_size`` items
        (non-blocking) from a given Queue. Does not mark the items as done.

        :rtype: Sequence
        :returns: A sequence of items retrieved from the queue.
        """
        items = [self._queue.get()]

        while len(items) < self._max_batch_size:
            try:
                items.append(self._queue.get_nowait())
            except queue.Empty:
                break

        return items