anchor.diff:      twitter-common-collections setproctitle ansicolors packaging pathspec
       scandir twitter-common-dirutil psutil requests pystache pex docutils
       markdown pygments twitter-common-confluence fasteners pywatchman
  -    futures cffi subprocess32 contextlib2 faulthandler pyopenssl
  +    futures cffi subprocess32 contextlib2 faulthandler pyopenssl wheel
     ];
   
     meta = {
  
positive.code: 
    src = fetchPypi {
      inherit pname version;
      sha256 = "7c0a1206594c615fce0a7f6daa4ea1028645bc20afa5599c2cf0ad7c06223fa7";
    };
  
    prePatch = ''
  
negative.code: with pythonPackages;
  
  let
    version = "1.6.0";
  in buildPythonApplication rec {
    inherit version;
    pname = "pantsbuild.pants";
  