new_contents: import bag_engine
  
  '''Generate .dot graph file. Format
  
  digraph G {
    1 [label = "room name #1"];
    2 [label = "room name #2"];
    1 -> 2 [label = "door going from room 1 to room 2"];
  }
  '''
  
  def create_graph(graph):
  
      room_num = 1
      room_name_to_number = {}
      for room in graph.keys():
          room_name_to_number[room] = room_num
          room_num += 1
  
      result = []
      for room in graph.keys():
          # output the room node
          room_number = room_name_to_number[room]
          result.append("  " + str(room_number) + ' [label = "' + room + '"];')
  
      for room in graph.keys():
          room_number = room_name_to_number[room]
  
          doors = graph[room]["doors"]
          for door in doors.keys():
              next_room = doors[door]
              next_room_number = room_name_to_number[next_room]
              result.append("  " + str(room_number) + " -> " + str(next_room_number) + ' [label = "' + door + '"];')
  
      return result
  
  
  graph = create_graph(bag_engine.g_rooms)
  
  output = open("bag_graph.dot", "w")
  output.write("digraph G {" + "\n")
  output.writelines("\n".join(graph))
  output.writelines("\n}\n")
  output.close()
  
subject: Add code to generate .dot file from room data