如何在用python重写行之前删除以前版本的行

我正在尝试更改文本文件中的某些信息。最初，文本文件看起来像

Entertainment
70
Clothing
15
Food
25

运行这个程序之后

import os, sys

import cs50

from cs50 import get_int

def main():

    print("Welcome to the money tracker program!")

    SpentOnEntertainment = get_int("How much money do you plan on spending on Entertainment? ")

    SpentOnClothing = get_int("How much money do you plan on spending on Clothing? ")

    SpentOnFood = get_int("How much money do you plan on spending on Food? ")

    Textfile = open("AFile2.txt", "r+")

    currentfunds = Textfile.readlines()

    if(SpentOnEntertainment > int(currentfunds[1])):

        print("Sorry, you can only spend", currentfunds[1], "dollars on Entertainment.")

        SpentOnEntertainment = int(currentfunds[1])

    currentfunds[1] = str(int(currentfunds[1]) - SpentOnEntertainment) + "\n"

    if(SpentOnClothing > int(currentfunds[3])):

        print("Sorry, you can only spend", currentfunds[3], "dollars on Clothing.")

        SpentOnClothing = int(currentfunds[3])

    currentfunds[3] = str(int(currentfunds[3]) - SpentOnClothing) + "\n"

    if(SpentOnFood > int(currentfunds[5])):

        print("Sorry, you can only spend", currentfunds[5], "dollars on Food.")

        SpentOnFood = int(currentfunds[5])

    currentfunds[5] = str(int(currentfunds[5]) - SpentOnFood) + "\n"

    Textfile.writelines(currentfunds)

    sys.exit(0)

if(__name__ == "__main__"):

    main()

这允许用户选择他们想要花多少钱，从而改变剩余的钱，新行被附加到我的原始行的末尾，我的最终结果（文本文件）是

我怎样才能摆脱前6行，因为它们不再相关？我尝试过在重读列表后使用诸如删除项目[0:6]之类的方法，但没有任何效果。

最简单的方法（我认为是）就是打开文件

读取文件并保存行

然后清空文件

Textfile = open("AFile2.txt", "r+") # open file
currentfunds = list(Textfile.readlines()) #save the lines
Textfile.close() #close the file
open('AFile2.txt', 'w').close() #empty the file
Textfile = open("AFile2.txt", "r+") # re-open file

---

谢谢，是的，我以w的形式再次打开文件，解决了这个问题+

Textfile = open("AFile2.txt", "r+") # open file
currentfunds = list(Textfile.readlines()) #save the lines
Textfile.close() #close the file
open('AFile2.txt', 'w').close() #empty the file
Textfile = open("AFile2.txt", "r+") # re-open file