anchor.diff:  
   let
   
  -  majorVersion = "5.3.1";
  +  majorVersion = "5.4.0";
     version = "${majorVersion}";
     libPrefix = "pypy${majorVersion}";
   
  
positive.code:       in ''
        patch lib-python/2.7/test/test_pyexpat.py < '${expatch}'
      '';
  
      buildInputs = [ bzip2 openssl pkgconfig pythonFull libffi ncurses expat sqlite tk tcl xlibsWrapper libX11 makeWrapper gdbm db ]
        ++ stdenv.lib.optional (stdenv ? cc && stdenv.cc.libc != null) stdenv.cc.libc
  
negative.code: 
      src = fetchurl {
        url = "https://bitbucket.org/pypy/pypy/get/release-pypy${pythonVersion}-v${version}.tar.bz2";
        sha256 = "1jm4ak6rbqhdhm8gjbd5hanabskbyzhzvjcl93fj0i017yirw88i";
      };
  
     # http://bugs.python.org/issue27369
  