Where is InputActionAssetReference?

Have gotten multiple compiler errors due to not having a namespace labelled InputActionAssetReference. Where is it supposed to be?

Assets\_Standard Assets\Characters\Scriptable Objects\Control Map\StandardControls.cs(9,33): error CS0246: The type or namespace name 'InputActionAssetReference' could not be found (are you missing a using directive or an assembly reference?)

[hunabku94]

that's probably because Input System evolved and removed "InputActionAssetReference".
It's strange unity not updated this script.