anchor.diff:  
   let
     version = "4.0.2";
  +
  +  # electrum is not compatible with dnspython 2.0.0 yet
  +  # use the latest 1.x release instead
  +  py = python3.override {
  +    packageOverrides = self: super: {
  +      dnspython = super.dnspython.overridePythonAttrs (oldAttrs: rec {
  +        version = "1.16.0";
  +        src = oldAttrs.src.override {
  +          inherit version;
  +          sha256 = "36c5e8e38d4369a08b6780b7f27d790a292b2b08eea01607865bf0936c558e01";
  +        };
  +      });
  +    };
  +  };
   
     libsecp256k1_name =
       if stdenv.isLinux then "libsecp256k1.so.0"
  
positive.code:   };
  in
  
  python3Packages.buildPythonApplication {
    pname = "electrum";
    inherit version;
  
  
negative.code:     wrapQtApp $out/bin/electrum
    '';
  
    checkInputs = with py.pkgs; [ pytest ];
  
    checkPhase = ''
      py.test electrum/tests
  