Кодирование картинок в base64

gistfile1.py

#!/usr/bin/env python
# coding: utf-8
import os
import urllib

def rel(*x):
    return os.path.join(os.path.abspath(os.path.dirname(__file__)), *x)

directory = rel()

ends = ('.jpg', '.png', '.gif')
f = open('codes.txt', 'ab')

images = filter(lambda x: x.endswith(ends), os.listdir(directory));

for a in images:
    encoded = urllib.quote(open(a, "rb").read().encode("base64"))
    ending = a.split('.')[1]
    base64 = 'data:image/%s;base64,' % ending
    f.write(a + '\n' + base64 + encoded + '\n\n')