now let's take a look at Qs a queue is a FIFO or first in first out data structure this is really intuitive because we see queues in every walk of life almost in everything you do on a daily basis you encounter queues queues have two key functions you in queue an item by adding it to the end of the line udq an item means removing it from the front of the line so some use cases for queues just about everything you wait in line for so bank tellers placing an order at McDonald's or your favorite restaurant DMV customer service supermarket checkout pretty much anything that has a line is what a queue is and it's important to be able to model that in a computer program so the queue data structure allows us to do that now let's take a look at how we can implement the queue in Python it's actually pretty simple because Python already provides us a built-in library called the deck or de quue that's a double-ended queue that allows you to add and remove items from both ends of the queue for our simple queue we don't really need that functionality we just want to be able to add items to one end of the queue and pop them off of the other so we can use the append function to add items or push items onto our queue and we can use pop left to remove items or pop items off of the cube you can see the full documentation in Python here if you want to learn more about how double into queues work so for basically just using double ended queue in Python as a single ended queue we can use from collections import deck that's going to import our double ended queue library and then we'll create a new queue my queue and that's going to be a double ended queue object and then we can append items or push items using the append function so we can push a 5 and we can push a tin onto the queue and then when we print out the queue we see that we have a double ended queue with a 5 and a 10 on it and then if we want to pop items off of the queue we use pop left and here we get to five that pops an item off the tail end of the queue or the left end of the queue so it's pretty easy to implement a queue in Python this is obviously a common enough data structure that Python built in a library for it now as a fun exercise for you you may try writing a wrapper class for the double-ended queue to make a single-ended queue using push and pop as we did similar for the stack