def parse_ticket(secret, ticket, ip, digest_algo=DEFAULT_DIGEST):
    """
    Parse the ticket, returning (timestamp, userid, tokens, user_data).

    If the ticket cannot be parsed, ``BadTicket`` will be raised with
    an explanation.
    """
    if isinstance(digest_algo, str):
        # correct specification of digest from hashlib or fail
        digest_algo = getattr(hashlib, digest_algo)
    digest_hexa_size = digest_algo().digest_size * 2
    ticket = ticket.strip('"')
    digest = ticket[:digest_hexa_size]
    try:
        timestamp = int(ticket[digest_hexa_size:digest_hexa_size + 8], 16)
    except __HOLE__ as e:
        raise BadTicket('Timestamp is not a hex integer: %s' % e)
    try:
        userid, data = ticket[digest_hexa_size + 8:].split('!', 1)
    except ValueError:
        raise BadTicket('userid is not followed by !')
    userid = url_unquote(userid)
    if '!' in data:
        tokens, user_data = data.split('!', 1)
    else:
        # @@: Is this the right order?
        tokens = ''
        user_data = data

    expected = calculate_digest(ip, timestamp, secret,
                                userid, tokens, user_data,
                                digest_algo)

    if expected != digest:
        raise BadTicket('Digest signature is not correct',
                        expected=(expected, digest))

    tokens = tokens.split(',')

    return (timestamp, userid, tokens, user_data)


# @@: Digest object constructor compatible with named ones in hashlib only
dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/Paste-2.0.1/paste/auth/auth_tkt.py/parse_ticket