anchor.diff:  
     checkInputs = [
       cssselect
  +    jaraco-test
       lxml
       mock
       pytestCheckHook
  
positive.code: 
  buildPythonPackage rec {
    pname = "cssutils";
    version = "2.4.0";
  
    disabled = pythonOlder "3.7";
  
  
negative.code: 
    src = fetchPypi {
      inherit pname version;
      sha256 = "877818bfa9668cc535773f46e6b6a46de28436191211741b3f7b4aaa64d9afbb";
    };
  
    nativeBuildInputs = [
      setuptools
      setuptools-scm
    ];
  
    propagatedBuildInputs = lib.optionals (pythonOlder "3.8") [
  