self: super: {
  python3 = super.python3.override {
    packageOverrides = python-self: python-super: {
      wokkel = python-self.buildPythonPackage rec {
        pname = "wokkel";
        version = "18.0.0";
        src = python-self.fetchPypi {
          inherit pname version;
          sha256 = "1spq44gg8gsviqx1dvlmjpgfc0wk0jpyx4ap01y2pad1ai9cw016";
        };
        propagatedBuildInputs = with python-self; [ twisted.extras.tls twisted incremental dateutil ];
        doChecks = false;
      };
    };
  };
}