python script that takes url encoded data in a file and decodes it

decode.py

#!/usr/bin/env python
import urllib

encoded_filename = urllib.quote('post.txt')
decoded_filename = 'post.txt.decode'
source = open(encoded_filename)
dest = open(decoded_filename, 'w')
decoded_data =  urllib.unquote_plus(source.read())
print decoded_data
dest.write(decoded_data)