anchor.diff:          --replace '@@taskwarrior@@' '${pkgs.taskwarrior}'
       '';
   
  -    buildInputs = with self; [ nose pkgs.taskwarrior ];
  +    buildInputs = with self; [ nose pkgs.taskwarrior tox ];
       propagatedBuildInputs = with self; [ six dateutil pytz ];
   
       meta = {
  
positive.code:     };
    };
  
    # TODO
    # Installs correctly but fails tests that involve simple things like:
    # cmd.run("tox", "-h")
    # also, buildPythonPackage needs to supply the tox.ini correctly for projects that use tox for their tests
    #
  
    tox = buildPythonPackage rec {
      name = "tox-1.7.2";
  
      propagatedBuildInputs = with self; [ py virtualenv ];
  
  
negative.code: 
      src = pkgs.fetchurl {
        url = "https://pypi.python.org/packages/source/t/tox/${name}.tar.gz";
        md5 = "c4423cc6512932b37e5b0d1faa87bef2";
      };
    };
  
  