If you need to mark a function, a class or a method as deprecated, you can use the @deprecated decorator. This documentation explains how to install and use the Python-Deprecated library. It includes a detailed tutorial and simple use cases. You will also have all the keys to contribute to the development of the source code. Why should you pay for this documentation? This a way to donate to the Python-Deprecated project. Your gratitude and financial help will be motivating to continue the project’s development.