python 遍历文件夹

本段python``代码可以遍历某个文件夹及其下所有子目录文件夹。
例如对所有文件重命名等。

import os
data_dir = "target_dir"
path = "/workspace/.../Data/"

def getFileList(dir, Filelist, ext=None):
	newDir = dir

	if os.path.isfile(dir):
		if ext is None:
			Filelist.append(dir)
			#or you can quit the program
		else:
			if ext in dir[-3:]:
				try:
					#你想对目标文件执行的操作
					os.rename(path + dir, path + dir.replace('.png', '.jpg'))
				except Exception as e:
					print(e)
				else:
					#操作成功print log
					print("rename" + dir + "success") 
				Filelist.append(dir)
		
		elif os.path.isdir(dir):
			for s in os.listdir(dir):
				newDir = os.path.join(dir,s)
				getFileList(newDir, Filelist, ext)

		return Filelist

imglist = getFileList(data_dir, [], 'png')