class composition in python with example

Composition is a concept that models a has a relationship. It enables creating complex types by combining objects of other types. This means that a class Composite can contain an object of another class Component. This relationship means that a Composite has a Component.

Example:

class Garage:

    def __init__(self, *cars):

        self.cars = cars

    def __str__(self):

        return (f"Total {len(self.cars)} cars in the Garage")

class Cars:

    def __init__(self, name, year):

        self.name = name

        self.year = year

    def __str__(self):

        return ("{} is moving to Garage in {}".format(self.name, self.year))

car = Cars("Ferrari", "2019")

car2 = Cars("Rolls", "2020")

car3 = Cars("Benz", "2021")

garage = Garage(car, car2, car3)

print(car)

print(car2)

print(car3)

print(garage)

Output:

Ferrari is moving to Garage in 2019
Rolls is moving to Garage in 2020
Benz is moving to Garage in 2021

Total 3 cars in the Garage