class Scene(object):

    def enter(self):
        pass

class Engine(object):

    def __init__(self, scene_map):
        pass

    def play(self):
        pass

class Death(Scene):

    def enter(self):
        pass

class CentralCorridor(Scene):

    def enter(self):
        pass

class TheBridge(Scene):

    def enter(self):
        pass

class EscapePod(Scene):

    def enter(self):
        pass

class Map(object):

    def __init__(self, start_scene):
        pass

    def next_scene(self, scene_name):
        pass

    def opening_scene(self):
        pass

a_map = Map("central_corridor")
a_game = Engine(a_map)
a_game.play()

Add initial code for exercise 43.
Add initial code for exercise 43.
