Getting ready for unit testing with pytest

So far, we have been writing code to add features to our RESTful Web Service and configuring many settings for the Django REST framework. We used command-line and GUI tools to understand how all the pieces worked together and to check the results of diverse HTTP requests. Now, we will write unit tests that will allow us to make sure that our RESTful Web Service will work as expected. Before we can start writing unit tests, it is necessary to install many additional packages in our virtual environment. Make sure you quit Django's development server. Remember that you just need to press Ctrl + C in the terminal or go to the Command Prompt window in which it is running. First, we will make some changes to work with a single version of our RESTful Web Service.

This way, it will be easier to focus on tests for a single version in our examples. Replace the code in the urls.py file in the restful01/restful01 folder, specifically, the restful01/restful01...