the next time the dequeue operation is calledthe while loop will not be executed because there are no elements in the outbound_stackwhich makes the outer if statement fail the pop operation is called right away in that case so that only the element in the queue that has waited the longest is returned typical run of code to use this queue implementation is as followsqueue queue(queue enqueue( queue enqueue( queue enqueue( print(queue inbound_stackqueue dequeue(print(queue inbound_stackprint(queue outbound_stackqueue dequeue(print(queue outbound_stackthe output for the preceding code is as follows[ [[ [ the code sample adds elements to queue and prints out the elements within the queue the dequeue method is calledafter which change in the number of elements is observed when the queue is printed out again implementing queue with two stacks is popular question posed during interviews node-based queue using python list to implement queue is good starter to get the feel of how queues work it is completely possible for us to implement our own queue data structure by utilizing our knowledge of pointer structures queue can be implemented using doubly linked listand insertion and deletion operations on this data structure have time complexity of (