'create a two-phase transaction ID.
this id will be passed to do_begin_twophase(), do_rollback_twophase(),
do_commit_twophase().  its format is unspecified.'

def create_xid(self):

    id = random.randint(0, (2 ** 128))
    return (4660, ('%032x' % id), ('%032x' % 9))
