Python 创建新文件时避免覆盖已有的同名文件的解决方法

import os

def check_filename_available(filename):
  n=[0]
  def check_meta(file_name):
    file_name_new=file_name
    if os.path.isfile(file_name):
      file_name_new=file_name[:file_name.rfind('.')]+'_'+str(n[0])+file_name[file_name.rfind('.'):]
      n[0]+=1
    if os.path.isfile(file_name_new):
      file_name_new=check_meta(file_name)
    return file_name_new
  return_name=check_meta(filename)
  return return_name
with open(check_filename_available('t.txt'),'w') as f:
  f.write('Checking func!')