1. class _IgnitionSystem(object):
2.    
3.    @staticmethod
4.    def produce_spark():
5.       return True
6.  
7. class _Engine(object):
8.  
9.    def __init__(self):
10.       self.revs_per_minute = 0
11.  
12.    def turnon(self):
13.       self.revs_per_minute = 2000
14.    
15.    def turnoff(self):
16.       self.revs_per_minute = 0
17.  
18. class _FuelTank(object):
19.    
20.    def __init__(self, level=30):
21.       self._level = level
22.    
23.    @property
24.    def level(self):
25.       return self._level
26.    
27.    @level.setter
28.         def level(self, level):
29.       self._level = level
30.  
31. class _DashBoardLight(object):
32.  
33.    def __init__(self, is_on=False):
34.       self._is_on = is_on
35.  
36.    def __str__(self):
37.       return self.__class__.__name__
38.  
39.    @property
40.    def is_on(self):
41.       return self._is_on
42.    
43.    @is_on.setter
44.    def is_on(self, status):
45.       self._is_on = status
46.    
47.    def status_check(self):
48.       if self._is_on:
49.          print("{}: ON".format(str(self)))
50.       else:
51.          print("{}: OFF".format(str(self)))
52.  
53. class _HandBrakeLight(_DashBoardLight):
54.    pass
55.  
56. class _FogLampLight(_DashBoardLight):
57.    pass
58.  
59. class _Dashboard(object):
60.    
61.    def __init__(self):
62.       self.lights = {"handbreak": _HandBrakeLight(), "fog": _FogLampLight()}
63.    
64.    def show(self):
65.            for light in self.lights.values():
66.       light.status_check()
67.  
68. # Facade
69. class Car(object):
70.    
71.    def __init__(self):
72.       self.ignition_system = _IgnitionSystem()
73.       self.engine = _Engine()
74.       self.fuel_tank = _FuelTank()
75.       self.dashboard = _Dashboard()
76.    
77.    @property
78.    def km_per_litre(self):
79.       return 17.0
80.    
81.    def consume_fuel(self, km):
82.       litres = min(self.fuel_tank.level, km / self.km_per_litre)
83.       self.fuel_tank.level -= litres
84.    
85.    def start(self):
86.       print("\nStarting...")
87.       self.dashboard.show()
88.       if self.ignition_system.produce_spark():
89.          self.engine.turnon()
90.       else:
91.          print("Can't start. Faulty ignition system")
92.    
93.    def has_enough_fuel(self, km, km_per_litre):
94.       litres_needed = km / km_per_litre
95.       if self.fuel_tank.level > litres_needed:
96.          return True
97.       else:
98.          return False
99.            
100.       def drive(self, km = 100):
101.          print("\n")
102.          if self.engine.revs_per_minute > 0:
103.             while self.has_enough_fuel(km, self.km_per_litre):
104.                self.consume_fuel(km)
105.                print("Drove {}km".format(km))
106.                print("{:.2f}l of fuel still left".format(self.fuel_tank.level))
107.          else:
108.             print("Can't drive. The Engine is turned off!")
109.          
110.          def park(self):
111.             print("\nParking...")
112.             self.dashboard.lights["handbreak"].is_on = True
113.             self.dashboard.show()
114.             self.engine.turnoff()
115.          
116.          def switch_fog_lights(self, status):
117.             print("\nSwitching {} fog lights...".format(status))
118.             boolean = True if status == "ON" else False
119.             self.dashboard.lights["fog"].is_on = boolean
120.             self.dashboard.show()
121.          
122.          def fill_up_tank(self):
123.             print("\nFuel tank filled up!")
124.             self.fuel_tank.level = 100
125.                                
126. # the main function is the Client
127. def main():
128.    car = Car()
129.    car.start()
130.    car.drive()
131.    car.switch_fog_lights("ON")
132.    car.switch_fog_lights("OFF")
133.         car.park()
134.    car.fill_up_tank()
135.    car.drive()
136.    car.start()
137.    car.drive()
138.  
139. if __name__ == "__main__":
140.    main()