anchor.diff:      owner = "jvoisin";
       repo = "mat2";
       rev = version;
  -    hash = "sha256-HjPr4pb0x2Sdq8ALaZeQRnGHmNAoEV8XUGbhOjY00jc=";
  +    hash = "sha256-H3l8w2F+ZcJ1P/Dg0ZVBJPUK0itLocL7a0jeSrG3Ws8=";
     };
   
     patches = [
  
positive.code:   '';
  
    nativeBuildInputs = [
      wrapGAppsHook
    ];
  
    buildInputs = [
      gdk-pixbuf
      gobject-introspection
      librsvg
      poppler_gi
    ];
  
negative.code: 
  buildPythonPackage rec {
    pname = "mat2";
    version = "0.13.0";
  
    disabled = pythonOlder "3.5";
  
  