librarian villager ID

Im making a plugin, and it includes one mob ID. I need a librarian villager ID, or something I can do to make a villager a librarian. I searched Google... Nothing.

Many thanks,
TheDeibo

pocketmine\entity\Villager.php

You can use Villager->setProfession()

hmm. So they is no ID then?

PROFESSION_LIBRARIAN = 1
NETWORK_ID = 15

villager's network_id=15
librarian's $namedtag->Profession=1

profession is in NBT, so I think there is no id.

It is an ID. Just that it isn't a unique entity ID, just like a dropped diamond has the same ID as a dropped dirt.