1.替换 import re file_name='new 4.txt' fp=open(file_name,'r') alllines=fp.readlines() fp.close() fp=open(file_name,'w') for eachline in alllines: a=re.sub('0.0.0.0','1.1.1.1',eachline) fp.wr

file_name=input('please input file name:') fp=open(file_name,'r') for i in range(20): print(fp.readline()) fp.close() input('press any key to exit')