anchor.diff:  
     doCheck = false;
   
  -  meta = with stdenv.lib; {
  +  meta = with lib; {
       description = "Foreign Function Interface for Python calling C code";
       homepage = http://cffi.readthedocs.org/;
       license = licenses.mit;
  
positive.code: }:
  
  let
    inherit (stdenv.lib)
      optionals;
  
    version = "1.10.0";
  
negative.code: { stdenv
  , buildPythonPackage
  , fetchPyPi
  , lib
  
  , libffi
  , pycparser
  