anchor.diff:  }:
   
   let
  -  inherit (stdenv.lib) optional optionalString concatStringsSep;
  +  inherit (stdenv.lib) optional optionals optionalString concatStringsSep;
     inherit (stdenv) isDarwin;
  +
   in buildPythonPackage rec {
     pname = "pandas";
     version = "0.23.1";
  
positive.code:                 "['pandas/src/klib', 'pandas/src', '$cpp_sdk']"
    '';
  
    checkPhase = ''
      runHook preCheck
    ''
  
negative.code:     chmod a+x pbcopy pbpaste
      export PATH=$(pwd):$PATH
    '' + ''
      py.test $out/${python.sitePackages}/pandas --skip-slow --skip-network -k "$disabledTests"
      runHook postCheck
    '';
  
  