anchor.diff:  { stdenv
   , lib
   , buildPythonPackage
  +, pythonOlder
   , fetchFromGitHub
   , six
  -, enum34
   , decorator
   , nose
   , krb5Full
   , darwin
  -, isPy27
   , parameterized
   , shouldbe
   , cython
  
positive.code: 
  buildPythonPackage rec {
    pname = "gssapi";
    version = "1.6.2";
  
    src = fetchFromGitHub {
      owner = "pythongssapi";
      repo = "python-${pname}";
      rev = "v${version}";
      sha256 = "195x3zqzyv491i9hf7l4asmic5pb2w3l1r7bps89651wkb3mrz1l";
    };
  
    # It's used to locate headers
  
negative.code:     six
    ];
  
    doCheck = pythonOlder "3.8"  # `shouldbe` not available
      && !stdenv.isDarwin;  # many failures on darwin
  
    # skip tests which fail possibly due to be an upstream issue (see
    # https://github.com/pythongssapi/python-gssapi/issues/220)
  