anchor.diff:      py.test
     '';
   
  +  # To prevent infinite recursion with pytest
  +  doCheck = false;
  +
     meta = with lib; {
       description = "Python attributes without boilerplate";
       homepage = https://github.com/hynek/attrs;
  
positive.code:   };
  
    # macOS needs clang for testing
    buildInputs = [
      pytest hypothesis zope_interface pympler coverage six
    ] ++ lib.optionals (stdenv.isDarwin) [ clang ];
  
  
negative.code: , pympler, coverage, six, clang }:
  
  buildPythonPackage rec {
    pname = "attrs";
    version = "17.4.0";
  
  