anchor.diff:      runHook postConfigure
     '';
   
  -  postInstall = ''
  +  postInstall = lib.optionalString (!isPy3k) ''
       # Let's make it a namespace package
       cat << EOF > $out/${python.sitePackages}/PyQt5/__init__.py
       from pkgutil import extend_path
  
positive.code:     qtbase
      qtsvg
      qtwebengine
    ];
  
    buildInputs = [
      sip
  
negative.code: in buildPythonPackage rec {
    pname = "PyQtWebEngine";
    version = "5.15.4";
    format = if isPy3k then "pyproject" else "other";
  
    src = pythonPackages.fetchPypi {
      inherit pname version;
  