"The goal of [defensive programming](https://en.wikipedia.org/wiki/Defensive_programming) is to try to maximize the reliability and overall quality of a piece of ...

Many languages, Python included, allow for assertions or assert statements. These are used to verify things you believe should be true about some condition or result. By making an assertion, you’re ...

Despite being a toy project, the goal is to have a working implementation. But performance is less important than documentation. Hence I focused on class contracts, since they are the most interesting ...