anchor.diff:  { lib
   , buildPythonPackage
   , fetchPypi
  -, python-dateutil
  +
  +# propagtes
   , sigtools
   , six
   , attrs
   , od
   , docutils
  +
  +# extras: datetime
  +, python-dateutil
  +
  +# tests
   , pygments
   , unittest2
   , pytestCheckHook
  
positive.code:     python-dateutil
      pygments
      unittest2
    ];
  
    propagatedBuildInputs = [
      attrs
      docutils
      od
      sigtools
      six
    ];
  
    pythonImportsCheck = [ "clize" ];
  
negative.code:     sha256 = "3177a028e4169d8865c79af82bdd441b24311d4bd9c0ae8803641882d340a51d";
    };
  
    postPatch = ''
      substituteInPlace setup.py \
        --replace "docutils ~= 0.17.0" "docutils"
    '';
  
    propagatedBuildInputs = [
      attrs
      docutils
      od
      sigtools
      six
    ];
  
    passthru.extras-require = {
      datetime = [
        python-dateutil
      ];
    };
  
    # repeated_test no longer exists in nixpkgs
    # also see: https://github.com/epsy/clize/issues/74
    doCheck = false;
  