text: import copy
  
  
  class Maze:
      def __init__(self):
          self._rooms = {}
  
      def add_room(self, room):
          self._rooms[room._room_number] = room
  
      def room_no(self, room_number):
          return self._rooms[room_number]
  
      def clone(self):
          return copy.deepcopy(self)
  