Alternatively, you can also change your stuff.gd
to not extend anything:
stuff.gd
var text
var size
func _init(t, s):
text = t
size = s
Then you can access it like that:
extends Node
const Stuff = preload("res://stuff.gd")
func _ready():
var inst = Stuff.new("fred", 100)
If you prefer to use subclasses with the class
keyword, you can do so, and then append .Stuff
after the preload like bitwes did.