{
   "answer" : {
      "bills" : [
         {
            "bill_id" : "123456",
            "old_pay_type" : "cash",
            "pay_status" : "payed",
            "pay_type" : "prepay",
            "result" : "success"
         }
      ]
   },
   "charset" : "utf-8",
   "messagestore" : null,
   "result" : "success"
}