Graphics.sprite base Object is show up as nil when extends

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1

Tips on what to include in your question:
I'm using the SDK in Windows and this is my first time using the SDK. I am trying to make a Projectile class and extend it to the sprite class. When I created the Projectile it showed "Load failed, error: CoreLibs/object.lua:65: field 'baseObject' is not callable (a nil value)" The only solution that I can come up with to remove the extend and create a sprite property.
show the code:

import "CoreLibs/object"


local pd <const> = playdate
local gfx <const> = pd.graphics

Projectile = {}
class('Projectile').extends(gfx.sprite)
function Projectile:init(image)
    
end
2

I think you have to import "CoreLibs/sprites" to use gfx.sprite as a class.