anchor.diff:    src = fetchPyPi {
       package = "Pillow";
       inherit version;
  -    sha256 = "0ee9975c05602e755ff5000232e0335ba30d507f6261922a658ee11b1cec36d1";
  +    sha256 = "a0fd487fed4a35717401b7566e51a1520b34e7c0f7f2a315a6509f82bc86299f";
     };
   
     buildInputs = [
  
positive.code: { stdenv
  , buildPythonPackage
  , fetchPyPi
  
  , freetype
  , lcms2
  , libjpeg
  , libtiff
  , libwebp
  , openjpeg
  , zlib
  }:
  
  let
    inherit (stdenv.lib)
      optionals;
  
    version = "3.4.2";
  in
  buildPythonPackage rec {
    name = "pillow-${version}";
  
negative.code:     libjpeg
      libtiff
      libwebp
      olefile
      openjpeg
      zlib
    ];
  