anchor.diff:  
       include = mkOption {
         type = types.listOf types.str;
  -      default = [];
  +      default = [ ];
         example = [ "/home" ];
         description = ''
           List of paths to include into the backups. See the FILE SELECTION
  
positive.code: 
      exclude = mkOption {
        type = types.listOf types.str;
        default = [];
        description = ''
          List of paths to exclude from backups. See the FILE SELECTION section in
          <citerefentry><refentrytitle>duplicity</refentrytitle>
  
negative.code: { config, lib, pkgs, ... }:
  
  with lib;
  let
    cfg = config.services.duplicity;
  
    stateDirectory = "/var/lib/duplicity";
  
    localTarget =
      if hasPrefix "file://" cfg.targetUrl
      then removePrefix "file://" cfg.targetUrl else null;
  
  in
  {
    options.services.duplicity = {
      enable = mkEnableOption "backups with duplicity";
  
  