composition_example.py

class Robot:

    def __init__(self, name, model_no, creator):
        self.name = name
        self.model_no = model_no
        self.creator = creator

    def walk(self):
        return 'I am walking using my wheels'

    def charge(self):
        return 'I am charging'


class Dog:

    def __init__(self, height, weight, species=None):
        self.species = species
        self.height = height
        self.weight = weight

    def speak(self):
        return 'Bow Bow'

    def walk(self):
        return 'I am walking using my legs'


class RoboDog:

    def __init__(self, name, model_no, creator, height, weight):
        self.robot_obj = Robot(name, model_no, creator)
        self.dog_obj = Dog(height, weight)

    def work(self):
        return 'Serve my Master'


Pika = RoboDog('Pika', 'rd-t1', 'Robo-Labs', '2', '5')

# In multiple inheritance: print(Pika.walk())

# In composition
print(Pika.robot_obj.walk())
print(Pika.dog_obj.speak())
print(Pika.work())