anchor.diff:  
     preBuild = ''
       sed -i 's,usr_share = .*,usr_share = "'$out'/share",g' setup.py
  -    pyrcc4 icons.qrc -o gui/qt/icons_rc.py
  +    pyrcc5 icons.qrc -o gui/qt/icons_rc.py
       # Recording the creation timestamps introduces indeterminism to the build
       sed -i '/Created: .*/d' gui/qt/icons_rc.py
     '';
  
positive.code:   postInstall = ''
      # Despite setting usr_share above, these files are installed under
      # $out/nix ...
      mv $out/lib/python2.7/site-packages/nix/store"/"*/share $out
      rm -rf $out/lib/python2.7/site-packages/nix
  
      substituteInPlace $out/share/applications/electrum.desktop \
        --replace "Exec=electrum %u" "Exec=$out/bin/electrum %u"
    '';
  
    doInstallCheck = true;
    installCheckPhase = ''
  
negative.code: { stdenv, fetchurl, python3, python3Packages }:
  
  python3Packages.buildPythonApplication rec {
    name = "electrum-${version}";
    version = "3.0.2";
  
    src = fetchurl {
      url = "https://download.electrum.org/${version}/Electrum-${version}.tar.gz";
      sha256 = "0lsg513lxs8qqpr7c0ibb7pma69hxiy3zqybganh6vs9byy7bzsd";
    };
  
    propagatedBuildInputs = with python3Packages; [
      dnspython
      ecdsa
      jsonrpclib-pelix
      matplotlib
      pbkdf2
      protobuf
      pyaes
      pycrypto
      pyqt5
      pysocks
      qrcode
      requests
  