anchor.diff:    src = fetchPyPi {
       package = "guessit";
       inherit version;
  -    sha256 = "a534a46bef3bbac7b313a55744860a9ddd5b7fae6abb6f6ae8bbace2b3e973b1";
  +    sha256 = "cdb51ced109e05318f35dc5ee1c50182a85edd800e86de77ec96eb68a0a99391";
     };
   
  -  buildInputs = optionals doCheck [
  +  nativeBuildInputs = optionals doCheck [
       pytest
       pytest-benchmark
       pytest-capturelog
  
positive.code: 
    doCheck = false;
  
    meta = with stdenv.lib; {
      description = "A library for guessing information from video filenames";
      homepage = https://pypi.python.org/pypi/guessit;
      license = licenses.lgpl3;
  
negative.code: { stdenv
  , buildPythonPackage
  , fetchPyPi
  , lib
  
  , babelfish
  , pytestrunner
  