Example 2

class Engine:
    def __init__(self):
        # how much the motor is spinning in revs per minute
        self.spin = 0

    def start(self, spin):
        self.spin = min(spin, 3000)


class StarterMotor:
    def __init__(self):
        # how much the starter motor is spinning in revs per minute
        self.spin = 0

    def start(self, charge):
        # if there is enough power then spin fast
        if (charge > 50):
            self.spin = 2500


class Battery:
    def __init__(self):
        # % charged, starts flat
        self.charge = 0


class Car:
    # the facade object that deals with the battery, engine and starter motor

    def __init__(self):
        self.battery = Battery()
        self.starter = StarterMotor()
        self.engine = Engine()

    def turn_key(self):
        self.starter.start(self.battery.charge)
        self.engine.start(self.starter.spin)
        if (self.engine.spin > 0):
            print("Engine started")
        else:
            print("Engine not started")

    def jump(self):
        self.battery.charge = 100
        print("Jumped")

from facade import Car

c = Car()
c.turn_key()  # engine not started because there is no charge

c.jump()
c.turn_key()  # engine starts because it has been charged