data = {
 "北京":{
  "昌平":{"沙河":["oldboy","test"],"天通苑":["链接地产","我爱我家"]},
  "朝阳":{"望京":["奔驰","陌陌"],"国贸":["CICC","HP"],"东直门":["advent","飞信"]},
  "海淀":{}
 },
 "山东":{
  "德州":{},
  "青岛":{},
  "济南":{}
 },
 "广东":{
  "东莞":{},
  "常熟":{},
  "佛山":{}
 }
}
exit_flag = False
while not exit_flag:
 for i in data:
  print(i)
 choice_s = input("请输入以上任一省或直辖市名称>:")
 if choice_s in data:
  while not exit_flag:
   for i in data[choice_s]:
    print("\t",i)
   choice_q = input("请输入以上任一市区名称>:")
   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("请输入以上任一街道名称>:")
     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("最后一层，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