anchor.diff:      "LD_LIBRARY_PATH=${cudaStub}\${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH} ";
   
   in buildPythonPackage rec {
  -  version = "0.4.1";
  +  version = "1.0.0";
     pname = "pytorch";
   
     src = fetchFromGitHub {
  
positive.code:     repo   = "pytorch";
      rev    = "v${version}";
      fetchSubmodules = true;
      sha256 = "1cr8h47jxgfar5bamyvlayvqymnb2qvp7rr0ka2d2d4rdldf9lrp";
    };
  
    preConfigure = lib.optionalString cudaSupport ''
  
negative.code: { buildPythonPackage, pythonOlder,
    cudaSupport ? false, cudatoolkit ? null, cudnn ? null,
    fetchFromGitHub, lib, numpy, pyyaml, cffi, typing, cmake, hypothesis,
    linkFarm, symlinkJoin,
    utillinux, which }:
  
  