PCAP - Python Certification Course

Object Oriented Programming

Overview Module 3

In this lesson, we revisit key programming paradigms and advanced techniques covered in Module 3, offering essential insights for writing robust and maintainable Python code.

Programming Paradigms

We began by exploring two major programming paradigms:

  • Procedural Approach: Functions operate on data without giving the data direct access to those functions.
  • Object-Oriented Approach: Objects interact by exchanging data and invoking methods. This paradigm enables a more dynamic and encapsulated design.

Object-Oriented Programming in Python

Python classes are central to object-oriented programming. In this module, we covered the following key concepts:

  • Instance Variables and Dynamic Properties: Learn to create instance variables and add properties dynamically.
  • Private Variables: Implement private variables by prefixing names with an underscore (e.g., _variable).
  • Class Methods: Understand how to define methods within classes, including the use of the constructor function and how the self parameter is automatically passed to every instance method.

We also examined how to use class introspection by exploring properties such as name, module, and bases, which are valuable for understanding class hierarchies and superclasses.

Note

Class introspection is a powerful tool for debugging and analyzing object behavior at runtime.

Advanced Object-Oriented Topics

We then delved into several advanced topics to further enhance your Python skills:

  • Introspection and Reflection: Use runtime methods to examine classes and objects.
  • Inheritance: Understand how classes inherit attributes and methods from superclasses, including the challenges of multiple inheritance.
  • Composition: Build objects by assembling other objects to achieve the desired behavior.
  • Method Resolution Order (MRO): Learn how Python determines the lookup order for attributes and methods, and how it handles complexities like the diamond problem in multiple inheritance.

Advanced Exception Handling

The module also enhanced your exception handling strategies by reviewing:

  • Else Block: Use an else block after an except block to execute code when no exception is raised in the corresponding try block.
  • Finally Block: Utilize a finally block to ensure that certain code always executes, regardless of whether an exception occurs.

Tip

Proper exception handling not only makes your code more robust but also facilitates easier debugging and maintenance.

Key Takeaways

ConceptDescriptionExample
Procedural ApproachFunctions operate on data that exist independently of those functions.--
Object-Oriented ApproachObjects communicate through methods and shared data, enabling encapsulation.--
Private VariablesUse underscores (e.g., _variable) to denote private class attributes.self._value
Method Resolution Order (MRO)Determines how Python looks up attributes or methods in a class hierarchy.--
Exception Handling (else)Executes code when no exception occurs in the try block.try: ... except: ... else: ...
Exception Handling (finally)Executes code regardless of whether an exception was raised.try: ... finally: ...

This module provided a comprehensive overview of fundamental and advanced object-oriented techniques in Python. For more details, refer to our Python Programming Guide and continue refining your coding expertise.

Watch Video

Watch video content

Previous
The objective nature of exceptions