错误操作

f = open("萝莉小姐姐电话号","r",encoding="gbk")
f.seek(-1)
print(f.read())

文件修改

f = open("萝莉小姐姐电话号","r",encoding="gbk")
s = f.read()
s1 = s.replace("你太美","吃煎饼")

f1 = open("萝莉小姐姐电话号","w",encoding="gbk")
f1.write(s1)

with 关键字 open("萝莉小姐姐电话号","r",encoding="gbk") as f:
  文件操作的具体内容

w,a 检测有文件就操作,没文件就创建

with open("萝莉小姐姐电话号","r",encoding="gbk")as f,\
        open("萝莉小姐姐电话号.txt","w",encoding="gbk")as f1:
    for i in f:
        s1 = i.replace("大烧饼","井盖")
        f1.write(s1)

import os
os.rename("萝莉小姐姐电话号","萝莉小姐姐电话号.bak")
os.rename("萝莉小姐姐电话号.txt","萝莉小姐姐电话号")

with open("萝莉小姐姐电话号","r",encoding="gbk")as f:
    pass # 缩进里操作文件
print(f.read())  # 文件及已经关闭了