anchor.diff:  }:
   
   let
  -  version = "8.1.1";
  +  version = "8.2.0";
   
     ptFiles = stdenv.mkDerivation {
       name = "PacketTracer8Drv";
  
positive.code:       cp "${desktopItem}"/share/applications/* "$out/share/applications/"
      '';
    };
  in stdenv.mkDerivation {
    pname = "ciscoPacketTracer8";
    inherit version;
  
  
negative.code:     dontUnpack = true;
      src = requireFile {
        name = "CiscoPacketTracer_${builtins.replaceStrings ["."] [""] version}_Ubuntu_64bit.deb";
        sha256 = "1b19885d59f6130ee55414fb02e211a1773460689db38bfd1ac7f0d45117ed16";
        url = "https://www.netacad.com";
      };
  
  