Can you give an example of using an aggregation method in object-oriented programming?

Aggregation in object-oriented programming is a 'part-whole' relationship where an object of one class contains a reference to an object of another class, but the objects can exist independently.

Example in Python:

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

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

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

engine = Engine()
car = Car(engine)
car.start()

Here, Car aggregates an Engine object. The Engine can exist independently of the Car. If the Car object is destroyed, the Engine can continue to exist.