We discuss one of the most important features of object-oriented programming, which is the ability to extend an existing class in order to get a new class that has behaviors modified from those of the existing class.

Read before lecture

Chapter 18 Sections 1 to 8
Pay particular attention to Section 18.7 Inheritance

Lecture materials

Slides: individual slides for viewing, 6-up layout for printing

Examples:

• shapes_v1.py version given before lecture
• shapes_v2.py version from lecture (added special string method)
• shapes_v3.py, draw_shapes.py OPTIONAL Turtle Graphics code--you do NOT need to know Turtle Graphics

Lecture Recording

Answers to the questions asked in lecture: Explore resolve_1_2.py, perhaps using Python Tutor, to get and understand the answers.