批量更改文件名

#!/usr/bin/env python
#coding=utf-8  
import os,sys
import shutil,re

def getparam(str):
    file_re=re.compile(r'(\w*)(#{1,})(\w*)')
    m=file_re.search(str)    
    return m.groups


def changename(dir):
    filenum=0
    i=int(sys.argv[3])
    list=os.listdir(dir)    
    for line in list:
        if os.path.isfile:            
            oldfullfile = dir+'\\'+line
            k=getparam(sys.argv[2])
            n=len(k(1)[1])
            ext = oldfullfile.split('.', 1)[1]   #get file_extension
            print('ext: '+ext)
            newfile=k(1)[0]+"{0:0{1}}".format(i,n)+k(1)[2]+'.'+ext  #format string filled by 0 
            print(newfile)
            newfullfile = dir+'\\'+newfile  
            print(oldfullfile)  
            print(newfullfile)  
            shutil.move(oldfullfile,newfullfile)  
            print(line)
            i=i+1

            
if len(sys.argv)!=4:
    print("arg count error")
else:
    #print(sys.argv[0])   #get python-name
    #print(sys.argv[2])
    k=getparam(sys.argv[2])
    changename(sys.argv[1])
    #print("{0:04}".format(5))

运行如：e:\python30\python BatchRename.py e:\myPython\rename  s####d  1
将把e:\myPython\rename下的文件都改为名为

s0001.py

s0002.py

........

最大

s9999.py

的形式