python————学习文件内容修改

f -open("yesterday2","r",encoding"utf-8")
f_new = open("yesterday2.bak","w",encoding"utf-8")  ##会生成f_new文件

for line in f:
    if"肆意的快乐等我享受" in line:  ##找到这个内容
        line = line.replace("此意的快乐等着我享受","此意的快乐等着小公子享受")  ##修改内容
    f_new.write(line)   ##无论判断是否成立都写入f_new
f.close()
f_new.close()