PriorityQueue

If we move away from our supermarket analogy and now think about an airport security area, there are some people who are more important than the regular customers. These are people like the pilots, the cabin crew, and others. In these exceptional circumstances, we'd typically move them up to the front of the queue so that they could proceed to get the planes in which we are about to fly to get them ready for takeoff.

In other words, we are giving them some form of priority within our queueing mechanism. Sometimes, in the systems that we develop, we need to also accommodate some form of prioritization mechanism so that incredibly important tasks aren't stuck behind millions of relatively unimportant operations for indefinite periods of time. This is where our PriorityQueue object comes into play.

With PriorityQueue, we can give everything that we put into the queue a weight as to how important it is. We can populate our PriorityQueues in much the same way that we populate our normal queue object except that we use tuples, and pass in priority_number as the first value in our tuple: (priority_number, data).