anchor.diff:    src = fetchPyPi {
       package = "greenlet";
       inherit version;
  -    sha256 = "0fef83d43bf87a5196c91e73cb9772f945a4caaff91242766c5916d1dd1381e4";
  +    sha256 = "9416443e219356e3c31f1f918a91badf2e37acf297e2fa13d24d1cc2380f8fbc";
     };
   
     # Builtin for pypy
  
positive.code: }:
  
  let
    version = "0.4.13";
  in
  buildPythonPackage rec {
    name = "greenlet-${version}";
  
negative.code: 
    meta = with lib; {
      description = "Module for lightweight in-process concurrent programming";
      homepage = https://github.com/python-greenlet/greenlet;
      license = licenses.lgpl2;
      maintainers = with maintainers; [
        codyopel
      ];
      platforms = with platforms;
        x86_64-linux;
    };
  