Example 2

# Adapter (source) interface
class EuropeanSocketInterface:
    def voltage(self): pass
    def live(self): pass
    def neutral(self): pass
    def earth(self): pass


# Target interface
class USASocketInterface:
    def voltage(self): pass
    def live(self): pass
    def neutral(self): pass


class EuropeanSocket(EuropeanSocketInterface):
    def voltage(self):
        return 230

    def live(self):
        return 1

    def neutral(self):
        return -1

    def earth(self):
        return 0


class AmericanKettle:
    __power = None

    def __init__(self, power):
        self.__power = power

    def boil(self):
        if self.__power.voltage() > 110:
            print("Kettle on fire!")
        else:
            if self.__power.live() == 1 and self.__power.neutral() == -1:
                print("Coffee time!")
            else:
                print("No power.")


class Adapter(USASocketInterface):
    __socket = None

    def __init__(self, socket):
        self.__socket = socket

    def voltage(self):
        return 110

    def live(self):
        return self.__socket.live()

    def neutral(self):
        return self.__socket.neutral()

from adapter import EuropeanSocket, AmericanKettle, Adapter

socket = EuropeanSocket()
kettle = AmericanKettle(socket)
kettle.boil()

adapter = Adapter(socket)
kettle = AmericanKettle(adapter)
kettle.boil()