为什么Python(使用3.7)重命名器不允许目录以数字开头?

我创建了下面的重命名器(如下)来替换文件名和目录名中的句点，这对于文件名来说似乎很好，但是对于以整数开头的目录名来说就不行了。不会产生任何错误。如果在任何目录名中都没有整数，那么它对目录是有效的。否则，它只是重命名文件，而不是目录。有人能告诉我为什么吗? 任何帮助都非常感谢。

import os

def Replace_Filename(Root_Folder):

    for Root, Dirs, Files in os.walk(Root_Folder):
       for File in Files:
        print(File)
        Fname, Fext = os.path.splitext(File)
        print(Fname)
        print(Fext)
        Replaced = Fname.replace(".","_")
        print(Replaced)
        New_Fname = Replaced + Fext
        print(New_Fname)
        F_path = os.path.join(Root, File)
        print(F_path)
        New_Fpath = os.path.join(Root, New_Fname)
        print(New_Fpath)
        os.rename(F_path, New_Fpath)


def Replace_Dirname(Root_Folder):

    for Root, Dirs, Files in os.walk(Root_Folder):
       for Dir in Dirs:
        print(Dir)
        New_Dname = Dir.replace(".","_")
        print(New_Dname)
        D_Path = os.path.join(Root, Dir)
        print(D_Path)
        New_Dpath = os.path.join(Root, New_Dname)
        print(New_Dpath)
        os.rename(D_Path, New_Dpath)




Root_Folder = "D:\\Practicerename-Copy"
Replace_Filename(Root_Folder)
Replace_Dirname(Root_Folder)

问题来源StackOverflow 地址：/questions/59379027/why-does-this-python-using-3-7-renamer-not-allow-directories-to-start-with-a-n