anchor.diff:    };
   
   
  -  # not sure if this is the best way to accomplish this -- needed to provide
  -  # objective-c compiler on darwin
  -  matplotlibStdenv = if stdenv.isDarwin
  -    then pkgs.clangStdenv
  -    else pkgs.stdenv;
  -
  -  # TODO: refactor to use pythonBuildPackage
  -  matplotlib = matplotlibStdenv.mkDerivation (rec {
  +  matplotlib = buildPythonPackage rec {
       name = "matplotlib-1.3.1";
   
       src = fetchurl {
  
positive.code:       sha256 = "0smgpn7lwbn02nbyhawyn0n6r3pb65zk501f21bjgavnjjfnf5pa";
      };
  
      # error: invalid command 'test'
      doCheck = false;
  
      buildInputs = [ python pkgs.which pkgs.ghostscript ];
  
      propagatedBuildInputs =
        [ dateutil nose numpy pyparsing tornado pkgs.freetype pkgs.libpng pkgs.pkgconfig pkgs.tcl
          pkgs.tk pkgs.xlibs.libX11 ];
      
      buildPhase = ''
        sed -i '/use_setuptools/d' setup.py
        ${python}/bin/${python.executable} setup.py build
      '';
  
      # The sed expression parses out the python version from an executable with appended characters
      installPhase = ''
        SITE="$out/lib/${python.libPrefix}/site-packages"
        mkdir -p "$SITE"
        PYTHONPATH="$PYTHONPATH:$SITE" ${python}/bin/${python.executable} setup.py install --prefix=$out
      '';
  
      meta = with stdenv.lib; {
        description = "python plotting library, making publication quality plots";
  
negative.code:       maintainers = with maintainers; [ lovek323 ];
        platforms   = platforms.unix;
      };
    };
  
  
    mccabe = buildPythonPackage (rec {
  