Summary

To summarize what we've learned so far, in State design patterns, the object's behavior is decided based on its state. The state of the object can be changed at runtime. Python's ability to change behavior at runtime makes it very easy to apply and implement the State design pattern. The State pattern also gives us control over deciding the states that objects can take up such as those in the computer example that we saw earlier in the chapter. The Context class provides an easier interface for clients, and ConcreteState makes sure it is easy to add behaviors to the objects. Thus, the State pattern improves cohesion, flexibility to extend, and removes redundant code blocks. We academically studied the pattern in the form of a UML diagram and learned about the implementation aspects of the State pattern with help of the Python v3.5 code implementation. We also took a look at the few pitfalls you might encounter when it comes to the State pattern, and the code which...