How to detect shirt template ID given a shirt ID?

Hey everyone! I want to make something where a player can enter the ID of a shirt they want to try on, and it puts it on their player. I know how to make most of this script, except for the part that gets the template ID from the shirt. Does anyone know how to do this? Thanks!

-- convert to template using a Decal 
local decal=Instance.new"Decal"
decal.Texture="https://www.roblox.com/catalog"..shirtid
local template=decal.Texture

Try adding this into a local script:

id = "choose your id"
game.Players.LocalPlayer.Shirt.ShirtTemplate = "rbxassetid://"..id