anchor.diff:  { lib
   , buildPythonPackage
  +, toPythonModule
   , isPy3k
   , pythonOlder
   , pythonAtLeast
  
positive.code:       "-DSMESH_LIB_PATH=${smesh}/lib"
        "-DPYTHONOCC_WRAP_SMESH=TRUE"
      ];
    };
  
  in
    buildPythonPackage rec {
  
negative.code: }:
  
  let
    pythonocc-core-cadquery = toPythonModule (stdenv.mkDerivation {
      pname = "pythonocc-core-cadquery";
      version = "0.18.2";
  
  