In this chapter, and indeed in this entire book, we have looked at how the application of modular programming techniques help you deal with the process of programming in the most effective way possible. Rather than avoiding change, you are able to manage it so that your code continues to work and is improved over time by the new requirements that are thrown at it.

We have looked at another example of a program that needed to be changed to meet an expanding set of requirements, and have seen how modular techniques, including the use of docstrings and unit tests, help to write robust and easy to understand code that improves as it continues to be developed and changed.

We have seen how the application of modular techniques is a vital part of dealing with the complexity of a program, and that this complexity only increases over time. We have learned that, because of this, the use of modular programming techniques is an essential part of what it means to be a good programmer. Finally, we have seen that modular techniques are something that can be used every time you sit down to program, even for simple throwaway scripts, and not something to be saved for your "big" projects.

I hope you have found this introduction to the world of modular programming useful, and are now starting to apply modular techniques and patterns to your own programming. I encourage you to continue to learn as much as you can about the various tools that surround good modular programming practice, such as the use of docstrings and the Sphinx library to auto-generate documentation for your packages, and the use of virtualenv to set up and use virtual environments to manage your program's package dependencies. The more you continue to use modular practices and techniques, the easier it will become—and the more effective you will be as a programmer. Happy coding!