python 实现批量替换文本中的某部分内容

import re
import os
 
 
def reset():
 
  i= 0
  path = r"/data/sdxx/mzq/YOLOv3/YOLOv3-New-fire/YOLOv3-SaveVideo-New/scripts/VOCdevkit/VOC2019/labels/"
  filelist = os.listdir(path)  # 该文件夹下所有文件（包括文件夹）
  for files in filelist: # 遍历所有文件
    i = i + 1
    Olddir = os.path.join(path,files); # 原来的文件路径
    if os.path.isdir(Olddir):
      continue;
 
    filename = os.path.splitext(files)[0];
    filetype = os.path.splitext(files)[1];
    filePath = path+filename+filetype
 
    alter(filePath,"16","1")
 
def alter(file,old_str,new_str):
 
  with open(file,"r",encoding="utf-8") as f1,open("%s.bak"% file,"w",encoding="utf-8") as f2:
    for line in f1:
 
 
      if old_str in line:
        line = line.replace(old_str,new_str)
 
      f2.write(line)
 
  os.remove(file)
  os.rename("%s.bak" % file,file)
 
reset()