def METHOD_NAME(root_id: str) -> str:
    # The regex pattern for an organizational unit ID string requires "ou-"
    # followed by from 4 to 32 lower-case letters or digits (the ID of the root
    # that contains the OU) followed by a second "-" dash and from 8 to 32
    # additional lower-case letters or digits.
    # e.g. ou-g8sd-5oe3bjaw
    return "-".join(
        [
            "ou",
            root_id.partition("-")[2],
            "".join(random.choice(CHARSET) for x in range(OU_ID_SUFFIX_SIZE)),
        ]
    )