学这么快！

您看一下，想要的结果是不是这样的：

import datetime

class Bank:

    summoney = 0

    def __init__(self):

        print('  交易日期\t\t\t摘要\t\t\t金额\t\t\t 币种\t\t\t余额')

    def save(self,type,money):

        print(datetime.date.today(),'\t\t\t'+type+'\t\t\t',money,'\t\t人民币\t\t\t',Bank.summoney+money)

        Bank.summoney =Bank.summoney+money

        return Bank.summoney

    def sell(self,type,money):

        print(datetime.date.today(),'\t\t\t'+type+'\t\t\t',money,'\t\t人民币\t\t\t',Bank.summoney-money)

        Bank.summoney =Bank.summoney-money

        return Bank.summoney

banksave =Bank()

Bank.summoney = 400

print(banksave.save('转入',80))

print(banksave.sell('转出',20))