anchor.diff:  buildPythonPackage rec {
     pname = "httpx";
     version = "0.21.3";
  +  format = "setuptools";
  +
     disabled = pythonOlder "3.6";
   
     src = fetchFromGitHub {
  
positive.code: { lib
  , buildPythonPackage
  , pythonOlder
  , fetchFromGitHub
  , brotlicffi
  , certifi
  , charset-normalizer
  , h2
  , httpcore
  , rfc3986
  , sniffio
  
negative.code:     brotlicffi
      certifi
      charset-normalizer
      httpcore
      rfc3986
      sniffio
    ] ++ lib.optionals (pythonOlder "3.7") [
      async_generator
    ];
  
    checkInputs = [
  