Can you give an example of composition usage in object-oriented programming?

Composition in object-oriented programming is when one object contains another object as part of its structure, and the lifecycle of the nested object depends on the external one.

Example in Python:

class Engine:
    def start(self):
        print("Engine started")

class Car:
    def __init__(self):
        self.engine = Engine()  # Composition: the car contains an engine

    def start(self):
        self.engine.start()
        print("Car is moving")

car = Car()
car.start()

Here, the Car object contains an Engine object. If the Car object is destroyed, the Engine also ceases to exist, which is the essence of composition.