anchor.diff:    buildInputs = with pkgs; [ alsaLib ffmpeg libv4l sqlite libvpx ];
     propagatedBuildInputs = [ cython pkgs.openssl dnspython dateutil xcaplib msrplib lxml python-otr ];
   
  -  meta = with stdenv.lib; {
  +  meta = with lib; {
       description = "SIP SIMPLE implementation for Python";
       homepage = http://sipsimpleclient.org/;
       license = licenses.gpl3;
  
positive.code: { stdenv
  , buildPythonPackage
  , fetchdarcs
  , isPy3k
  , pkgs
  , cython
  
negative.code: 
  buildPythonPackage rec {
    pname = "sipsimple";
    version = "3.4.2";
    disabled = isPy3k;
  
    src = fetchFromGitHub {
      owner = "AGProjects";
      repo = "python-sipsimple";
      rev = "release-${version}";
      sha256 = "094xf343d6zjhg9jwbm3dr74zq264cyqnn22byvm2m88lnagmhmr";
    };
  
    preConfigure = ''
  