主函数

def convert_currency(im, er):
    out = im * er
    return out


def main():
    USD_VS_RMB = 6.77
    # 带单位的货币输入
    currency_str_value = input(‘请输入带单位的货币金额：‘)
    unit = currency_str_value[-3:]
    if unit == ‘CNY‘:
        exchange_rate = 1 / USD_VS_RMB
    elif unit == ‘USD‘:
        exchange_rate = USD_VS_RMB
    else:
        exchange_rate = -1
    if exchange_rate != -1:
        in_money = eval(currency_str_value[:-3])
        # 调用函数
        out_money = convert_currency(in_money, exchange_rate)
        print(‘转换后的金额：‘, out_money)
    else:
        print(‘不支持该种货币！‘)


if __name__ == ‘__main__‘:

             main()