How can I use Python's "unittest" library to write unit tests for a Django application and integrate them into a CI/CD pipeline?

Start by creating test cases first. These test classes should inherit from `unittest.TestCase`, and you should define the test methods within these classes to cover specific functionality. Then, use the following command to execute your unit tests locally:

./manage.py test

In your CI/CD configuration, set up a test stage that runs the Django test runner, and ensure that it's triggered whenever changes are pushed to the repository. If necessary, test your Django application on multiple Python versions to ensure compatibility. Nevertheless, remember to configure your pipeline to fail if any unit tests fail.