anchor.diff:  , buildPythonPackage
   , fetchPyPi
   , isPy27
  +, lib
   
   , botocore
   , futures
  
positive.code:     futures
    ];
  
    meta = with stdenv.lib; {
      description = "An Amazon S3 Transfer Manager";
      homepage = https://github.com/boto/s3transfer;
      license = licenses.asl20;
  
negative.code:   inherit (stdenv.lib)
      optionals;
  
    version = "0.1.10";
  in
  buildPythonPackage rec {
    name = "s3transfer-${version}";
  