def METHOD_NAME(calnet_uid: str) -> List[Any]:
    def flatten(lst: Iterator[Any]) -> List[Any]:
        return [item for sublist in lst for item in sublist]
    group_accounts = flatten(
        map(
            lambda group: group['accounts'],
            groups_by_student_signat(calnet_uid).values(),
        ),
    )
    # sanity check since we don't trust CalLink API that much:
    # if >= 10 groups, can't change online, sorry
    assert len(group_accounts) < 10, 'should be less than 10 group accounts'
    return group_accounts