'For grading--return just the chosen child.'

def get_child_descriptors(self):

    group_id = self.get_group_id()
    if (group_id is None):
        return []
    str_group_id = str(group_id)
    if (str_group_id in self.group_id_to_child):
        child_location = self.group_id_to_child[str_group_id]
        child_descriptor = self.get_child_descriptor_by_location(child_location)
    else:
        log.debug('configuration    error    in    split    test    module:    invalid    group_id    %r    (not    one    of    %r).        Showing    error', str_group_id, self.group_id_to_child.keys())
    if (child_descriptor is None):
        log.debug('configuration    error    in    split    test    module:    no    such    child')
        return []
    return [child_descriptor]
