anchor.diff:  
   in pythonPackages.buildPythonApplication rec {
     pname = "beets";
  -  version = "1.4.7";
  +  version = "1.4.9";
   
     src = fetchFromGitHub {
       owner = "beetbox";
       repo = "beets";
       rev = "v${version}";
  -    sha256 = "17gfz0g7pqm6wha8zf63zpw07zgi787w1bjwdcxdh1l3z4m7jc9l";
  +    sha256 = "1qxdqbzvz97zgykzdwn78g2xyxmg0q2jdb12dnjnrwvhmjv67vi8";
     };
   
     propagatedBuildInputs = [
  
positive.code: , enableKeyfinder      ? true, keyfinder-cli ? null
  , enableKodiupdate     ? true
  , enableLastfm         ? true
  , enableMpd            ? true
  , enableReplaygain     ? true, bs1770gain ? null
  , enableSonosUpdate    ? true
  , enableThumbnails     ? true
  , enableWeb            ? true
  
  
negative.code:     kodiupdate = enableKodiupdate;
      lastgenre = enableLastfm;
      lastimport = enableLastfm;
      loadext = enableLoadext;
      mpdstats = enableMpd;
      mpdupdate = enableMpd;
      playlist = enablePlaylist;
      replaygain = enableReplaygain;
      sonosupdate = enableSonosUpdate;
      subsonicupdate = enableSubsonicupdate;
      thumbnails = enableThumbnails;
      web = enableWeb;
    };
  