anchor.diff:  , cryptography
   , curve25519-donna
   , ecdsa
  -, ed25519
   , fetchFromGitHub
   , h11
   , pyqrcode
  
positive.code: 
  buildPythonPackage rec {
    pname = "hap-python";
    version = "3.5.1";
    disabled = pythonOlder "3.6";
  
    # pypi package does not include tests
    src = fetchFromGitHub {
      owner = "ikalchev";
      repo = "HAP-python";
      rev = "v${version}";
      sha256 = "sha256-ZHTqlb7LIDp8MFNW8MFg6jX7QwaxT40cLi3H13ONLCI=";
    };
  
    propagatedBuildInputs = [
  
negative.code:     cryptography
      curve25519-donna
      ecdsa
      h11
      pyqrcode
      zeroconf
  