anchor.diff:      # install_requires
       jaraco_functools
   
  -    more-itertools six
  +    more-itertools
  +    six
     ];
   
     checkInputs = [
  
positive.code: { lib, stdenv, fetchPypi, buildPythonPackage, isPy3k
  , jaraco_functools
  , jaraco_text
  , more-itertools
  
negative.code:     rm pytest.ini
    '';
  
    disabledTests = [
      "tls" # touches network
      "peercreds_unix_sock" # test urls no longer allowed
    ] ++ lib.optionals stdenv.isDarwin [
      "http_over_https_error"
      "bind_addr_unix"
    ];
  
    disabledTestFiles = [
      # avoid attempting to use 3 packages not available on nixpkgs
      # (jaraco.apt, jaraco.context, yg.lockfile)
      "cheroot/test/test_wsgi.py"
    ];
  
    # Some of the tests use localhost networking.
  