docs: def validate_event_and_assign_id(event):
    """
    Ensure that the event has a valid time. Assign a random UUID based on the
    event time.
    """
    event_time = event.get(TIMESTAMP_FIELD)
  
    if event_time is None:
      event[TIMESTAMP_FIELD] = event_time = epoch_time_to_kronos_time(time.time())
    elif type(event_time) not in (int, long):
      raise InvalidEventTime(event_time)
  
    # Generate a uuid1-like sequence from the event time with the non-time bytes
    # set to random values.
    _id = uuid_from_kronos_time(event_time)
    event[ID_FIELD] = str(_id)
    return _id, event