anchor.diff:      click-plugins
       six
       munch
  -  ] ++ stdenv.lib.optional (!isPy3k) enum34;
  +  ] ++ lib.optional (!isPy3k) enum34;
   
     checkInputs = [
       pytest
       boto3
  -  ] ++ stdenv.lib.optional (pythonOlder "3.4") mock;
  +  ] ++ lib.optional (pythonOlder "3.4") mock;
   
     checkPhase = ''
       rm -r fiona # prevent importing local fiona
  
positive.code: { stdenv, buildPythonPackage, fetchPypi, isPy3k, pythonOlder
  , attrs, click, cligj, click-plugins, six, munch, enum34
  , pytest, boto3, mock
  , gdal_2 # can't bump to 3 yet, https://github.com/Toblerity/Fiona/issues/745
  }:
  
  
negative.code: 
    buildInputs = [
      gdal_2
    ] ++ lib.optionals stdenv.cc.isClang [ giflib ];
  
    propagatedBuildInputs = [
      attrs
  