python 修改后缀名

使用到的模块
os.walk
os.path.join
os.path.splitext
os.rename 重命名文件

import os
from tqdm import tqdm
import time

filenames = os.listdir()
#print(os.walk(os.getcwd()))
for dirpath, dirname, filenames in os.walk(os.getcwd()):
    #print(dirpath, dirname, filenames)
    for filename in filenames:
        old_filename = os.path.join(dirpath,filename)
        filename_list = os.path.splitext(old_filename)
        if filename_list[-1]==".JPG":
            newname = filename_list[0] + ".jpg"
            os.rename(old_filename,newname)

print("over!")
#for i in filenames:
#    if ".JPG" in i:
#        i.replace(".JPG",".jpg")