实现简单的shell sed替换功能

 1 import sys
 2 
 3 f=open('lyrics.txt','r',encoding='utf-8')  #读写
 4 f_new=open('lyrics_new','w+',encoding='utf-8')
 5 find_str=sys.argv[1]
 6 replace_str=sys.argv[2]
 7 for line in f:
 8     if find_str in line:
 9         line=line.replace(find_str,replace_str)
10     f_new.write(line)
11 f.close()
12 f_new.close()