Factory Method

factory_method.py

class Computer:
    @staticmethod
    def factory(type):
        computers = {
            'Macbook': Macbook,
            'Surface': Surface,
            'Desktop': Desktop
        }
        try:
            return computers[type]()
        except KeyError:
            raise NotImplementedError('Computer version not implemented')


class Macbook:
    def os_version(self):
        return 'OSX Sierra'


class Surface:
    def os_version(self):
        return 'Windows 10'


class Desktop:
    def os_version(self):
        return 'Windows 7'


macbook = Computer.factory('Macbook')
print(macbook.os_version())

surface = Computer.factory('Surface')
print(surface.os_version())