Python test cases are used to check the correctness of the business logic. In Chapter 6, Basic Server-Side Development, you saw how you can modify the business logic of the existing app. This makes it even more important, as customization might break the app's functionality. In this chapter, we will write a test case to validate the business logic to change the book's state.
Python test cases
Getting ready
We will be using the my_library module from the Chapter18/r0_initial_module directory of the GitHub repository.
How to do it...
Follow these steps to add Python...
