Python批量修改文件名

import os

def renamefile():
    path=input("输入文件夹路径：")
    try:
        filelist=os.listdir(path)
    except:
        print('找不到指定路径')
        return
    if path[-1:]=='\\'  :
        path=path
    else:
        path=path+'\\'
    try:
        for f in filelist:
            oldname=path+os.path.splitext(f)[0]+os.path.splitext(f)[1]#文件名
            prefixname=os.path.splitext(f)[0]#文件名前缀和后缀
            prefixname=prefixname.split('_')#按_分割
            newname=path+prefixname[1]+os.path.splitext(f)[1]#新文件名
            os.rename(oldname,newname)
            print(oldname+"->"+newname)
    except:
        print('文件名不正确,{0}'.format(prefixname))
        return


if __name__=='__main__':
    renamefile()