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Marlon Munoz
Marlon Munoz

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PYTHON: OOP {Beginner's Edition}

Python: Object-Oriented Programming [OOP]: is a programming paradigm (model) that uses objects and classes to structure software in a way that models real-world entities and relationships. This is based on the idea that objects can contain data and code that manipulates that data.

There are key concepts you need to know about Object-Oriented Programming:

  1. Class
  2. Object
  3. Attributes
  4. Methods
  5. Inheritance
  6. Encapsulation
  7. Polymorphism
  8. Abstraction

The example below, is an example to help you reference the concepts being explained and to give you a graphical idea of how each concept looks like inside of on object, if you are starting to learn OOP, this will help you grasp what each concept is doing.



class Car:
    def __init__(self, make, model, year, color):
        self.__make = make
        self.model = model
        self.year = year
        self.color = color

    def drive(self):
        print(f"The {self.year} {self.__make} {self.model} is driving")

# GETTER method for make
    def get_make(self):
        return self.__make

# SETTER method for make
    def set_make(self, make):
        self.__make = make


class ElectricCar(Car):
    def __init__(self, make, model, year, battery_size):
        super().__init__(make, model, year)
        self.battery_size = battery_size

    def drive(self):
        print(f"The {self.year} {self.make} {self.model} with a 
{self.battery_size}-kWh battery is driving silently.")

my_car = Car("McLaren Automotive", "Artura Spider", 2024, "Red/Black")
my_electric_car.drive()


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What is a Class:?
In Python, a Class: is a blueprint for creating objects. It defines a set of attributes and methods that the created objects will have. For instance, you can quickly define a class like this:



class Car:


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What is an Object?
In Python, and object is an instance of a class. It is created using the class blueprint and can have its own unique data. For example you can create an object like this:



my_car = Car("McLaren Automotive", "Artura Spider", 2024, "Red/Black")
my_electric_car


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What are Attributes?
In Python, attributes are variables that belong to a class or an object. They represent the state or data of the object. An example of an attribute looks like this:



    self.color = color


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What are Methods?
In Python, methods are functions that belong to a class. They define behaviors or actions that the objects can perform. An example of a method looks like this:
TIP: when defining a method, you can add pass; temporally so that python won't throw an error when running the file.



    def drive(self):
        pass;  


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What is Inheritance?
In Python, an Inheritance is a mechanism where a new class (child class) inherits attributes and methods from an existing class (parent class). An example:

ElectricCar inherits from Car



class ElectricCar(Car):


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What is Encapsulation?
Encapsulation in a bundling of data (attribute) and methods that operate on the data into a single unit (class), and restricting access to some of the object's components. In addition, you can make it a private variable by prefixing it with double underscores __. Additionally, you should provide a getter and a setter methods to access and modify the private variable.
For example, you can set a private variable like this:



self.__make = make


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And add the Setter and Getter to access and modify the private variable



    # Getter method for make
    def get_make(self):
        return self.__make

    # Setter method for make
    def set_make(self, make):
        self.__make = make


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Getter Method: get_make method is added to access the private variable __make

Setter Method: set_make method is added to modify the private variable __make

This encapsulates the make attribute, ensuring it is not directly accessible from outside the class, thus providing better encapsulation and control over the attribute.

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