anchor.diff:      hash = "sha256-qrrxZHeAal4d0ZqkH4wreVDdPHRjYtfjIj2+beasRI4=";
     };
   
  -  propagatedBuildInputs = [
  -    brotli
  -    pysocks
  -  ] ++ lib.optionals isPy27 [
  -    cryptography
  -    idna
  -    pyopenssl
  -  ];
  +  # FIXME: remove backwards compatbility hack
  +  propagatedBuildInputs = passthru.optional-dependencies.brotli
  +    ++ passthru.optional-dependencies.secure;
   
     checkInputs = [
       python-dateutil
  
positive.code: { lib
  , brotli
  , buildPythonPackage
  , cryptography
  , python-dateutil
  , fetchPypi
  , idna
  , isPy27
  , mock
  , pyopenssl
  , pysocks
  
negative.code:     "urllib3"
    ];
  
    passthru.optional-dependencies = {
      brotli = if isPyPy then [ brotlicffi ] else [ brotli ];
      secure = [ certifi cryptography idna pyopenssl ];
      socks = [ pysocks ];
    };
  
    meta = with lib; {
      description = "Powerful, sanity-friendly HTTP client for Python";
      homepage = "https://github.com/shazow/urllib3";
  