url_safe_uuid.py

#!/usr/bin/python
# Generate URL-safe UUID/GUIDs in Python, e.g.
#
#   ob9G9Ju_Re6SRgxacdUzhw
#   k0CWKgThQq-9b2ZcmpVXXA
#

# base64 has an urlsafe encoding
from base64 import urlsafe_b64encode

# any of uuid1, uuid3, uuid4 or uuid5 will do
# see http://docs.python.org/2/library/uuid.html
from uuid import uuid4 as uuid

# generate a uuid and base64 encode it
# drop trailing "==", add it back if decoding
print urlsafe_b64encode(uuid().bytes)[0:22]