#!/usr/bin/envpython3#-*-coding:utf-8-*-#fromcollectionsimportnamedtuple#定义一个命名元组来存储赎回费率的期限和费率RedemptionRate=namedtuple("RedemptionRate",["days","rate"])defcalculate_costs(P,T,F_A,M_A,S_A,T_A,R_A