anchor.diff:  , cudatoolkit_11_3
   , cudatoolkit_11_4
   , cudatoolkit_11_5
  +, cudatoolkit_11_6
   , fetchurl
   , lib
   }:
  
positive.code:     cudatoolkit = cudatoolkit_10_2;
      # See https://docs.nvidia.com/deeplearning/cudnn/archives/cudnn-832/support-matrix/index.html#cudnn-cuda-hardware-versions.
      minCudaVersion = "10.2.00000";
      maxCudaVersion = "11.5.99999";
      mkSrc = cudatoolkit:
        let v = if lib.versions.majorMinor cudatoolkit.version == "10.2" then "10.2" else "11.5"; in
        fetchurl {
  
negative.code:   cudnn_8_3_cudatoolkit_11_3 = cudnn_8_3_cudatoolkit_10_2.override { cudatoolkit = cudatoolkit_11_3; };
    cudnn_8_3_cudatoolkit_11_4 = cudnn_8_3_cudatoolkit_10_2.override { cudatoolkit = cudatoolkit_11_4; };
    cudnn_8_3_cudatoolkit_11_5 = cudnn_8_3_cudatoolkit_10_2.override { cudatoolkit = cudatoolkit_11_5; };
    cudnn_8_3_cudatoolkit_11_6 = cudnn_8_3_cudatoolkit_10_2.override { cudatoolkit = cudatoolkit_11_6; };
  
    cudnn_8_3_cudatoolkit_10 = cudnn_8_3_cudatoolkit_10_2.override { cudatoolkit = cudatoolkit_10; };
    cudnn_8_3_cudatoolkit_11 = cudnn_8_3_cudatoolkit_10_2.override { cudatoolkit = cudatoolkit_11; };
  