anchor.diff:        --replace "test_rename_dir_to_existing_dir" "notest_rename_dir_to_existing_dir"
     '');
   
  -  # https://github.com/jmcgeheeiv/pyfakefs/issues/508
  -  doCheck = !isPy37;
     checkInputs = [ pytest glibcLocales ];
   
     checkPhase = ''
  
positive.code:     description = "Fake file system that mocks the Python file system modules";
      license     = licenses.asl20;
      homepage    = "http://pyfakefs.org/";
      maintainers = with maintainers; [ gebner ];
    };
  }
  
negative.code: { stdenv, buildPythonPackage, fetchPypi, pythonOlder, python, pytest, glibcLocales }:
  
  buildPythonPackage rec {
    version = "4.1.0";
    pname = "pyfakefs";
    disabled = pythonOlder "3.5";
  
    src = fetchPypi {
      inherit pname version;
  