This lesson plan is designed for intermediate Python programmers who have a fundamental understanding of Python syntax and basic programming concepts. The focus will be on deepening the understanding of object-oriented programming (OOP) by exploring classes, their structure, methods, attributes, inheritance, and more. We aim to provide a comprehensive overview with practical examples and exercises to solidify the concepts discussed.
By the end of this lesson, students will be able to:
- Define and explain the purpose and structure of classes in Python.
- Understand and implement class methods and attributes.
- Utilize initializers and understand the significance of
self
. - Apply inheritance to create a hierarchy of classes.
- Differentiate between instance methods, class methods (@classmethod), and static methods (@staticmethod).
- Definition and Purpose: Explain what classes are and why they are useful in programming.
- Basic Structure: Introduction to the basic structure of a class.
- Example 1: Creating a simple class
Car
with attributes and a method.
- Example 1: Creating a simple class
- Instance Methods: How to define methods and use
self
to access attributes. - Class Attributes vs. Instance Attributes: The difference between attributes shared among all instances of a class and those unique to each instance.
- Example 2: Enhancing the
Car
class with instance methods and both types of attributes.
- Example 2: Enhancing the
- Using
__init__
: How to initialize instance attributes. - Inheritance and
super()
: How to use inheritance to extend classes andsuper()
to call the parent class's initializer.- Exercise 1: Create a
ElectricCar
class that inherits fromCar
and add an additional attribute.
- Exercise 1: Create a
- Creating Subclasses: How to create a class that inherits from another class.
- Overriding Methods: How to modify or extend the functionality of inherited methods.
- Exercise 2: Override a method in the
ElectricCar
class to include charging information.
- Exercise 2: Override a method in the
- Static Methods: How and when to use static methods.
- Class Methods: How and when to use class methods and the purpose of the
cls
parameter.- Group Discussion: Discuss scenarios where
staticmethods
andclassmethods
might be useful.
- Group Discussion: Discuss scenarios where
- Exercise 3: Implement a class method in the
Car
class that tracks the number of cars created. - Exercise 4: Create a static method in the
Car
class that calculates the miles per gallon (MPG) given distance and fuel usage.
- Recap of the key points covered in today's lesson.
- Open floor for any questions and clarifications.
Create an ElectricCar
class that inherits from the Car
class. Add an initializer that includes a battery size attribute, and ensure it calls the parent class's initializer with super()
.
Within the ElectricCar
class, override a method to display information about the car, including its battery size and a message saying it's electric.
Add a class attribute to the Car
class to keep track of how many cars have been created. Implement a class method get_car_count
that returns the number of car instances created.
Implement a static method in the Car
class named calculate_mpg
that takes distance and fuel used as parameters and returns the miles per gallon.