NPC Use?

Garry's Mod coding
#1

So I’ve made a SNPC, and I want people to be able to press use on it.
I have this in init.lua, because it’s for the server, but it doesn’t work
[lua]

function ENT:Use( activator, caller )
print(“sup”);
if ( activator:IsPlayer() ) then
print(“is player!”)
end
end
[/lua]

#2 

SNPC:SetUseType( SIMPLE_USE )

NPC Shop Tutorial

#3

Ah! That’s the tutorial I was looking for, but found this one