Outline:

1. Recap: dict type
   • Exercise from last time: practice with dicts
2. Features of object-oriented design
   • encapsulation
   • polymorphism
   • inheritance
3. Inheritance
   • parent and child classes (aka superclasses and subclasses)
   • Exercise 1: exploring graphics.py
   • is-a versus has-a

Explore after class:

4. More practice working with dictionaries
   • example: finding the key with the highest value (check Slack)
5. Reading code with inheritance
   • Exercise 2

Reading assignment (to be completed by the next class):

• Zelle chapter 12 (pp. 419-456) - especially sec. 12.4-12.5 (pp. 451-456)