TOPT Codes

gistfile1.py

import time
import hmac
import struct
import base64
import hashlib

def code(secret):
    key = base64.b32decode(secret)
    message = struct.pack(">Q", int(time.time()) / 30)
    h = hmac.new(key, message, hashlib.sha1).digest()
    offset = ord(h[19]) & 0xF
    code = (struct.unpack(">I", h[offset:offset+4])[0] & 0x7FFFFFFF) % 1E6
    print "{0:06n}".format(code)

code("AAAAAAAAAAAAAAAA")