python 批量将jpeg\png等其他后缀改成jpg后缀

代码

import os
import string
dirName = "JPEGImages\\"         #最后要加双斜杠，不然会报错
li=os.listdir(dirName)
for filename in li:
    newname = filename
    newname = newname.split(".")
    if newname[-1]=="jpeg":
        newname[-1]="jpg"
        newname = str.join(".",newname)  #这里要用str.join
        filename = dirName+filename
        newname = dirName+newname
        os.rename(filename,newname)
        print(newname,"updated successfully")
    if newname[-1]=="png":
        newname[-1]="jpg"
        newname = str.join(".",newname)  #这里要用str.join
        filename = dirName+filename
        newname = dirName+newname
        os.rename(filename,newname)
        print(newname,"updated successfully")