Topic
1. Create Class & Object2. Instance vs Class Variables3. Constructors in Python Classes4. Single Inheritance5. Multiple Inheritance6. Multilevel Inheritance7. Polymorphism with Methods8. Method Overloading Simulation9. Encapsulation with Getters/Setters10. Abstraction with ABC11. Operator Overloading12. Custom Iterator13. Class Methods14. Static Methods15. Composition Example16. Aggregation Example17. Private Variables18. Magic Methods Overview19. Object Cloning20. Custom Exceptions21. Class Decorator22. Prototype Pattern23. Singleton Pattern24. MRO (Method Resolution Order) Demo25. Polymorphism (Duck Typing)

Polymorphism (Duck Typing) in Python

Use duck typing to write functions that work with any object having the required method.

IntermediateObject-Oriented ProgramsExample 25 of 25
polymorphism-duck-typing.py
1# Program to demonstrate polymorphism via duck typing
2

3class FileLogger:
4    def write(self, message):
5        print("[File]", message)
6

7class ConsoleLogger:
8    def write(self, message):
9        print("[Console]", message)
10

11def log_something(logger):
12    logger.write("Logging an event")
13

14log_something(FileLogger())
15log_something(ConsoleLogger())

Output

[File] Logging an event
[Console] Logging an event

What's going on

The function 'log_something' relies only on the presence of a 'write' method, not on concrete types.

After this program

If the idea is still fuzzy, read Day 11: Classes and Objects in the Python course. For a short check, try the Python quiz (300 questions). Stay with all 25 object-oriented programs, or see every topic on Python exercises.

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