修改源文件的内容到新文件

1、写死要替换的内容

__Author__ = "Devin"
f1 = open("song",'r',encoding='utf-8')
f2 = open("song.bak",'w',encoding='utf-8')
for line in f1:
    if "寻找一个我属于的地方" in line:
        line = line.replace("寻找一个我属于的地方","寻找一个*****devin*****属于的地方")
    f2.write(line)
f1.close()
f2.close()

 2、根据传递的参数[1]、[2]修改内容

__Author__ = "Devin"
import sys
f1 = open("song",'r',encoding='utf-8')
f2 = open("song.bak",'w',encoding='utf-8')

find_str = sys.argv[1]
replace_str = sys.argv[2]

for line in f1:
    if find_str in line:
        line = line.replace(find_str,replace_str)
    f2.write(line)
f1.close()
f2.close()