In the previous recipes, test writing was covered, but there is an important aspect to testing called coverage. Coverage determines how much of our code has been covered by the tests. The higher the percentage of coverage, the better our tests (although it's not the only criterion for good tests). In this recipe, we will check the code coverage of our application.
Tip
Remember that 100 percent test coverage does not mean that the code is flawless. However, in any case, it is better than having no tests or lower coverage. Anything that is not tested is broken.
We will use a library called coverage for this recipe. The following is the installation command:
$ pip install coverage