anchor.diff:  
   buildPythonPackage rec {
     pname = "tensorflow-tensorboard";
  -  version = "2.4.0";
  +  version = "2.6.0";
     format = "wheel";
  -  disabled = !isPy3k;
  +  disabled = pythonOlder "3.6";
   
     src = fetchPypi {
       pname = "tensorboard";
       inherit version format;
  +    dist = "py3";
       python = "py3";
  -    sha256 = "0f17h6i398n8maam0r3rssqvdqnqbwjyf96nnhf482anm1iwdq6d";
  +    sha256 = "sha256-99rEzftS0UyeP3RYXOKq+OYgNiCoZOUfr4SYiwn3u9s=";
     };
   
  +  postPatch = ''
  +    chmod u+rwx -R ./dist
  +    pushd dist
  +    wheel unpack --dest unpacked ./*.whl
  +    pushd unpacked/tensorboard-${version}
  +
  +    substituteInPlace tensorboard-${version}.dist-info/METADATA \
  +      --replace "google-auth (<2,>=1.6.3)" "google-auth (<3,>=1.6.3)"
  +
  +    popd
  +    wheel pack ./unpacked/tensorboard-${version}
  +    popd
  +  '';
  +
     propagatedBuildInputs = [
  +    absl-py
  +    grpcio
  +    google-auth-oauthlib
  +    markdown
       numpy
  -    werkzeug
       protobuf
  -    markdown
  -    grpcio
  -    absl-py
  -    google-auth-oauthlib
  +    setuptools
  +    tensorboard-data-server
       tensorboard-plugin-profile
       tensorboard-plugin-wit
  +    werkzeug
       # not declared in install_requires, but used at runtime
       # https://github.com/NixOS/nixpkgs/issues/73840
       wheel
  
positive.code: 
    meta = with lib; {
      description = "TensorFlow's Visualization Toolkit";
      homepage = "http://tensorflow.org";
      license = licenses.asl20;
      maintainers = with maintainers; [ abbradar ];
    };
  
negative.code: , markdown
  , absl-py
  , google-auth-oauthlib
  , setuptools
  , tensorboard-data-server
  , tensorboard-plugin-wit
  , tensorboard-plugin-profile
  }:
  