Python Lessons 5: Object Oriented Programming: A Tutorial
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Our Journey to Object Oriented Programming Begins
Hello friends! After learning basic data types, variables, conditional expressions, loops, functions, lists, dictionaries and file operations in Python, we are now ready to step into the world of object-oriented programming (OOP).
OOP is a powerful programming paradigm used to develop large and complex software. This paradigm simulates real-world objects, making the code more streamlined, reusable, and maintainable.
Basic Concepts of OOP: Objects and Classes
The building blocks of OOP are objects and classes. A class is a template of objects with similar properties and behaviors. An object is an instance of a class. For example, let's take the "Car" class. This class can have properties such as number of wheels, color, brand, and behaviors such as acceleration and braking. A "BMW" or a "Ford" car are instances of the "Car" class.
Classes and Objects: A Practical Example
Here is an example of creating a class and object in Python:
```python class Car: """Car class.""" def __init__(self brand model color): """Initializes the Car object.""" self.brand = brand self.model = model self.color = color def show_info(self): """Shows information about the car.""" print(f"Brand: {self.brand}") print(f"Model: {self.model}") print(f"Color: {self.color}") # Creating an object from the Car class mycar = Car("BMW" "5 Series" "Black") # Showing information about the car mycar.show_info() ```
In this example, we defined a class named Car . The __init__() method is called when an instance of the class is created and initializes the object's properties. The info_show() method prints the car's information to the screen.
4 Key Features of OOP: Encapsulation, Abstraction, Inheritance and Polymorphism
OOP has four key features that make code more reusable and easier to maintain:
Encapsulation: Encapsulation is the process of combining data and methods into a single unit.
For example, in a "Car" class, data such as number of wheels, color, and brand, and methods such as acceleration and braking will be encapsulated. This prevents accidental modification of the data and makes the code more secure.
Abstraction: Abstraction is the process of hiding the complex internal structure of an object and showing only the important features and behaviors.
For example, in a "Car" class, the user only sees the functions of the car, such as accelerating, braking and steering; he does not need to know the internal mechanisms of the car.
Inheritance: Inheritance is the process of transferring properties and methods from one class to another.
For example, the "SportsCar" class can inherit from the "Car" class and add a property such as "turbo" or a method such as "turbo_ac".
Polymorphism: Polymorphism allows the same named method to be implemented differently by different classes.
For example, classes "Car" and "SportsCar" may have a method called "accelerate", but this method may be implemented differently by each class.
Benefits of OOP: More Powerful, More Flexible and More Reusable Code
Using OOP makes code more powerful, more flexible, and more reusable.
Powerful: OOP allows code to be more organized and modular, which makes it easier to find and fix bugs.
Flexible: OOP allows the code to be more flexible because inheritance can be used between classes and new classes can be created easily.
Reusable: OOP makes code more reusable because classes can be used over and over again in different parts of the program.
