local plastic_itemstring
if minetest.get_modpath("basic_materials") then
	plastic_itemstring = "basic_materials:plastic_sheet"
elseif minetest.get_modpath("luxury_decor") then
	plastic_itemstring = "luxury_decor:plastic_sheet"
else
	error("'plastic_sheet' crafting element is required to be registered!")
end

minetest.register_craft({
	output = "adv_vehicles:car_frame",
	recipe = {
                  {plastic_itemstring, plastic_itemstring, plastic_itemstring},
                  {plastic_itemstring, plastic_itemstring, plastic_itemstring},
                  {plastic_itemstring, "", ""}
                 }
})