anchor.diff:    ];
   
     propagatedBuildInputs = [
  -    appdirs
  +    backports-entry-points-selectable
       distlib
       filelock
  +    platformdirs
       six
  -  ] ++ lib.optionals isPy27 [
  -    contextlib2
  -  ] ++ lib.optionals (isPy27 && !stdenv.hostPlatform.isWindows) [
  +  ] ++ lib.optionals (pythonOlder "3.4" && !stdenv.hostPlatform.isWindows) [
       pathlib2
     ] ++ lib.optionals (pythonOlder "3.7") [
       importlib-resources
  
positive.code: { buildPythonPackage
  , appdirs
  , contextlib2
  , cython
  , distlib
  , fetchPypi
  
negative.code: , flaky
  , importlib-metadata
  , importlib-resources
  , pathlib2
  , platformdirs
  , pytest-freezegun
  , pytest-mock
  , pytest-timeout
  , pytestCheckHook
  , setuptools-scm
  , six
  }:
  
  buildPythonPackage rec {
    pname = "virtualenv";
    version = "20.7.2";
  
    src = fetchPypi {
      inherit pname version;
      sha256 = "9ef4e8ee4710826e98ff3075c9a4739e2cb1040de6a2a8d35db0055840dc96a0";
    };
  
    nativeBuildInputs = [
  