Change the file extension for files in a folder?

Question

I would like to change the extension of the files in specific folder. i read about this topic in the forum. using does ideas, I have written following code and I expect that

Answer 1

Something like this will rename all files in the executing directory that end in .txt to .text

import os, sys

for filename in os.listdir(os.path.dirname(os.path.abspath(__file__))):
  base_file, ext = os.path.splitext(filename)
  if ext == ".txt":
    os.rename(filename, base_file + ".text")