def addtext(txtname,span,insert):
txtfile=open(txtname);
txt=txtfile.readlines()
txt=['auto+'+line for line in txt]
txtfile.close()
txtfile=open(txtname,'w')
i=0
while i+span txtfile.writelines(txt[i:i+span])
txtfile.write(insert)
txtfile.write('\n')
i+=span
txtfile.writelines(txt[i:len(txt)])
txtfile.close()
addtext('list.txt',2,'the laber')
每隔两行添加一个the laber,如果希望改变间隔将代码最后一行中间的数字2改变就行了
