docs: def uuidToOoid(uuid,timestamp=None, depth= None):
    """ Create an ooid from a 32-hex-digit string in regular uuid format.
    uuid: must be uuid in expected format: xxxxxxxx-xxxx-xxxx-xxxx-xxxxx7777777
    timestamp: the year-month-day is encoded in the ooid. If none, use current day
    depth: the expected storage depth is encoded in the ooid. If non, use the defaultDepth
    returns a new opaque id string holding the first 24 digits of the provided uuid and encoded date and depth info
    """
    if not timestamp:
      timestamp = utc_now().date()
    if not depth:
      depth = defaultDepth
    assert depth <= 4 and depth >=1
    return "%s%d%02d%02d%02d" %(uuid[:-7],depth,timestamp.year%100,timestamp.month,timestamp.day)