data = { "北京":{  "昌平":{"沙河":["oldboy","test"],"天通苑":["鏈接地產","我愛我家"]},  "朝陽":{"望京":["奔馳","陌陌"],"國貿":["CICC","HP"],"東直門":["advent","飛信"]},  "海淀":{} }, "山東":{  "德州":{},  "青島":{},  "濟南":{} }, "廣東":{  "東莞":{},  "常熟":{},  "佛山":{} }}exit_flag = Falsewhile not exit_flag: for i in data:  print(i) choice_s = input("請輸入以上任一省或直轄市名稱>>>:") if choice_s in data:  while not exit_flag:   for i in data[choice_s]:    print("/t",i)   choice_q = input("請輸入以上任一市區名稱>>>:")   if choice_q in data[choice_s]:    while not exit_flag:     for i in data[choice_s][choice_q]:      print("/t/t",i)     choice_j = input("請輸入以上任一街道名稱>>>:")     if choice_j in data[choice_s][choice_q]:      for i in data[choice_s][choice_q][choice_j]:       print("/t/t",i)      last = input("最后一層，按b返回>>>:")      if last == "b":       pass      elif last == "q":       exit_flag = True     if choice_j == "b":      break     elif choice_j == "q":      exit_flag = True   if choice_q == "b":    break   elif choice_q == "q":    exit_flag = True