[Python module] queue

8.8. queue — A synchronized queue class¶
queue -- 一个同步队列类
The queue module implements multi-producer, multi-consumer queues. It is especially useful in threaded programming when information must be exchanged safely between multiple threads. The Queue class in this module implements all the required locking semantics. It depends on the availability of thread support in Python; see the threading module.
queue模块处理多生产者和多消费者的队列。在多线程间信息的安全交换非常有用。这个module的Queue类处理所需的locking语义，它依赖于threading模块。
Implements three types of queue whose only difference is the order that the entries are retrieved. In a FIFO queue, the first tasks added are the first retrieved. In a LIFO queue, the most recently added entry is the first retrieved (operating like a stack). With a priority queue, the entries are kept sorted (using the heapq module) and the lowest valued entry is retrieved first.
三种类型的队列，FIFO，LIFO，以及优先队列（使用heapq模块，先取得低优先级）。
The queue module defines the following classes and exceptions:
class queue.Queue(maxsize)¶Constructor for a FIFO queue. maxsize is an integer that sets the upperbound limit on the number of items that can be placed in the queue. Insertion will block once this size has been reached, until queue items are consumed. If maxsize is less than or equal to zero, the queue size is infinite.
创建FIFP队列。maxsiaze <= 0, 无限制
class queue.LifoQueue(maxsize)¶Constructor for a LIFO queue. maxsize is an integer that sets the upperbound limit on the number of items that can be placed in the queue. Insertion will block once this size has been reached, until queue items are consumed. If maxsize is less than or equal to zero, the queue size is infinite.
创建LIFO队列。maxsiaze <= 0, 无限制
class queue.PriorityQueue(maxsize)¶
Constructor for a priority queue. maxsize is an integer that sets the upperbound limit on the number of items that can be place