nixos-hardware/lenovo/thinkpad/x13/default.nix

{
  assertions = [
    {
      assertion = false;
      message = "Importing the x13/ (default.nix) directly is deprecated! See https://github.com/NixOS/nixos-hardware/blob/master/lenovo/thinkpad/x13/OLD-BEHAVIOUR-DEPRECATED.md for more details.";
    }
  ];
}