anchor.diff:  { lib
   , buildPythonPackage
   , fetchFromGitHub
  -, isPy27
  +, pythonOlder
  +, dataclasses
   , kafka-python
   , cython
   , zlib
  
positive.code: 
  buildPythonPackage rec {
    pname = "aiokafka";
    version = "0.7.0";
  
    disabled = isPy27;
  
    src = fetchFromGitHub {
      owner = "aio-libs";
      repo = "aiokafka";
      rev = "v${version}";
      sha256 = "16pcgv38syqy6sj3w7zx95zgynpd642n3i95dpiw0ivhpqrxxhrf";
    };
  
    nativeBuildInputs = [
  
negative.code: 
    propagatedBuildInputs = [
      kafka-python
    ] ++ lib.optionals (pythonOlder "3.7") [
      dataclasses
    ];
  
    # checks require running kafka server
    doCheck = false;
  
    pythonImportsCheck = [ "aiokafka" ];
  
    meta = with lib; {
      description = "Kafka integration with asyncio";
  