Software can easily be applied and distributed. But in some cases, it needs to be extensible. When your software is packed and deployed, there might still be amendments to be done. Or - when you develop a software development kit - maybe the software consists of many many libraries that should be mixed together. Why not try python? It has some nice features built-in that can easily be used to develop libraries that still work together. Join me on mild trip through the land of decorators, entry-points, namespace packages and protocol classes.