Shortest possible generated unique ID

So we can generate a unique id with str(uuid.uuid4()), which is 36 characters long.

Is there another method to generate a unique ID which is shorter in terms of characters?

EDIT:

• If ID is usable as primary key then even better
• Granularity should be better than 1ms
• This code could be distributed, so we can't assume time independence.

If this is for use as a primary key field in db, consider just using auto-incrementing integer instead.

str(uuid.uuid4()) is 36 chars but it has four useless dashes (-) in it, and it's limited to 0-9 a-f.

Better uuid4 in 32 chars:

>>> uuid.uuid4().hex
'b327fc1b6a2343e48af311343fc3f5a8'

Or just b64 encode and slice some urandom bytes (up to you to guarantee uniqueness):

>>> base64.b64encode(os.urandom(32))[:8]
b'iR4hZqs9'