anchor.diff:  
   buildPythonPackage rec {
     pname = "jupytext";
  -  version = "1.13.2";
  +  version = "1.13.3";
     format = "pyproject";
   
     disabled = pythonOlder "3.6";
  
positive.code:     owner = "mwouts";
      repo = pname;
      rev = "v${version}";
      sha256 = "sha256-S2SKAC2oT4VIVMMDbu/Puo87noAgnQs1hh88JphutA8=";
    };
  
    buildInputs = [
  
negative.code:   postPatch = ''
      # https://github.com/mwouts/jupytext/pull/885
      substituteInPlace setup.py \
        --replace "markdown-it-py~=1.0" "markdown-it-py>=1.0.0,<3.0.0"
    '';
  
    preCheck = ''
  