Introduction
                        
                            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.  There are three types of queues provides by queue module,Which are as following :   1. Queue  2. LifoQueue  3. PriorityQueue  Exception which could be come:   1. Full (queue overflow)  2. Empty (queue underflow)