anchor.diff:    version = "0.19.0";
     disabled = isPy27;
   
  -  src = fetchPypi {
  -    inherit pname version;
  -    sha256 = "cbcdc826915dd07f7df723bec0dd3edd5e61e54c40e7a8b023e19d4434eef602";
  +  src = fetchFromGitHub {
  +    owner = "optuna";
  +    repo = pname;
  +    rev = "v${version}";
  +    sha256 = "179x2lsckpmkrkkdnvvbzky86g1ba882z677qwbayhsc835wbp0y";
     };
   
     checkInputs = [
  
positive.code:     mxnet
      scikit-optimize
      tensorflow
    ];
  
    propagatedBuildInputs = [
  
negative.code:     colorlog
      pandas
      alembic
      tqdm
    ] ++ lib.optionals (pythonOlder "3.5") [
      typing
    ];
  
    configurePhase = if !(pythonOlder "3.5") then ''
      substituteInPlace setup.py \
        --replace "'typing'," ""
    '' else "";
  
    checkPhase = ''
      pytest --ignore tests/test_cli.py \
             --ignore tests/integration_tests/test_chainermn.py \
             --ignore tests/integration_tests/test_pytorch_lightning.py \
             --ignore tests/integration_tests/test_pytorch_ignite.py \
             --ignore tests/integration_tests/test_fastai.py
    '';
  
    meta = with lib; {
  