Design Patterns in Python: Elegant Solutions

Learning Objectives: After this lesson, you'll implement classic design patterns the Pythonic way, understand when to use each pattern, and build flexible, maintainable code using Factory, Strategy, Observer, Decorator, and Dependency Injection patterns.

Why Design Patterns?

Design patterns are reusable solutions to common programming problems.

Patterns in Python

Creational Patterns

Factory Pattern

Singleton Pattern

Builder Pattern

Behavioral Patterns

Strategy Pattern

Observer Pattern

Command Pattern

Structural Patterns

Decorator Pattern (Structural)

Adapter Pattern

Dependency Injection

Practice Exercises

Exercise 1: Plugin System

Exercise 2: State Machine

Key Takeaways

Pythonic Alternatives

Next Steps

In the next lesson, we'll explore Packaging and Distribution—modern Python packaging with pyproject.toml, dependency management, and publishing to PyPI.

Ready to ship your code? Packaging awaits!