anchor.diff:  
       "itsdangerous" = python.mkDerivation {
         name = "itsdangerous-1.1.0";
  -      src = pkgs.fetchurl { url = "https://files.pythonhosted.org/packages/68/1a/f27de07a8a304ad5fa817bbe383d1238ac4396da447fa11ed937039fa04b/itsdangerous-1.1.0.tar.gz"; sha256 = "321b033d07f2a4136d3ec762eac9f16a10ccd60f53c0c91af90217ace7ba1f19"; };
  -      doCheck = commonDoCheck;
  -      checkPhase = "";
  -      installCheckPhase = "";
  -      buildInputs = commonBuildInputs;
  -      propagatedBuildInputs = [ ];
  -      meta = with pkgs.stdenv.lib; {
  -        homepage = "";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/68/1a/f27de07a8a304ad5fa817bbe383d1238ac4396da447fa11ed937039fa04b/itsdangerous-1.1.0.tar.gz";
  +        sha256 = "321b033d07f2a4136d3ec762eac9f16a10ccd60f53c0c91af90217ace7ba1f19";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [ ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "https://palletsprojects.com/p/itsdangerous/";
           license = licenses.bsdOriginal;
           description = "Various helpers to pass data to untrusted environments and back.";
         };
       };
   
  +    "jinja2" = python.mkDerivation {
  +      name = "jinja2-2.10.1";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/93/ea/d884a06f8c7f9b7afbc8138b762e80479fb17aedbbe2b06515a12de9378d/Jinja2-2.10.1.tar.gz";
  +        sha256 = "065c4f02ebe7f7cf559e49ee5a95fb800a9e4528727aec6f24402a5374c65013";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [
  +        self."babel"
  +        self."markupsafe"
  +      ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "http://jinja.pocoo.org/";
  +        license = licenses.bsdOriginal;
  +        description = "A small but fast and easy to use stand-alone template engine written in pure python.";
  +      };
  +    };
  +
  +    "markdown" = python.mkDerivation {
  +      name = "markdown-2.6.11";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/b3/73/fc5c850f44af5889192dff783b7b0d8f3fe8d30b65c8e3f78f8f0265fecf/Markdown-2.6.11.tar.gz";
  +        sha256 = "a856869c7ff079ad84a3e19cd87a64998350c2b94e9e08e44270faef33400f81";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [ ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "https://Python-Markdown.github.io/";
  +        license = licenses.bsdOriginal;
  +        description = "Python implementation of Markdown.";
  +      };
  +    };
  +
  +    "markupsafe" = python.mkDerivation {
  +      name = "markupsafe-1.1.1";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/b9/2e/64db92e53b86efccfaea71321f597fa2e1b2bd3853d8ce658568f7a13094/MarkupSafe-1.1.1.tar.gz";
  +        sha256 = "29872e92839765e546828bb7754a68c418d927cd064fd4708fab9fe9c8bb116b";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [ ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "https://palletsprojects.com/p/markupsafe/";
  +        license = licenses.bsd3;
  +        description = "Safely add untrusted strings to HTML/XML markup.";
  +      };
  +    };
  +
       "marshmallow" = python.mkDerivation {
  -      name = "marshmallow-3.0.0b20";
  -      src = pkgs.fetchurl { url = "https://files.pythonhosted.org/packages/9b/dd/c6125334e434794754bf7fdc85bd9a26bdd3b1734471562a2b1ccd6e5802/marshmallow-3.0.0b20.tar.gz"; sha256 = "0a96d88418c4e7c50a39a734c4ed3d2a991a37e6b7a8970dbbdb8ccb7f08ecb0"; };
  -      doCheck = commonDoCheck;
  -      checkPhase = "";
  -      installCheckPhase = "";
  -      buildInputs = commonBuildInputs;
  -      propagatedBuildInputs = [ ];
  -      meta = with pkgs.stdenv.lib; {
  -        homepage = "";
  +      name = "marshmallow-3.0.0rc6";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/91/0d/c91fc9cbc7e737ddc01d5b55900d7611ea52bd24c0660ea2e4df1a3e0ac9/marshmallow-3.0.0rc6.tar.gz";
  +        sha256 = "8c6a22cfc9ca33945e2707c771c44030a035be96082a18643d431280b9b8f08e";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [ ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "https://github.com/marshmallow-code/marshmallow";
           license = licenses.mit;
           description = "A lightweight library for converting complex datatypes to and from native Python datatypes.";
         };
       };
   
  -    "more.forwarded" = python.mkDerivation {
  -      name = "more.forwarded-0.2";
  -      src = pkgs.fetchurl { url = "https://files.pythonhosted.org/packages/7c/d8/e14f30346a9da2dc705f2206a04c70d40dc03e8238f3a9ac4bb668aedb25/more.forwarded-0.2.tar.gz"; sha256 = "d6e89b4990dc98fe4476d1dea3c49506a3434d5fc8118d48afaeecfcaa0595c3"; };
  -      doCheck = commonDoCheck;
  -      checkPhase = "";
  -      installCheckPhase = "";
  -      buildInputs = commonBuildInputs;
  -      propagatedBuildInputs = [
  -      self."morepath"
  -    ];
  -      meta = with pkgs.stdenv.lib; {
  -        homepage = "";
  +    "marshmallow-enum" = python.mkDerivation {
  +      name = "marshmallow-enum-1.5.1";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/8e/8c/ceecdce57dfd37913143087fffd15f38562a94f0d22823e3c66eac0dca31/marshmallow-enum-1.5.1.tar.gz";
  +        sha256 = "38e697e11f45a8e64b4a1e664000897c659b60aa57bfa18d44e226a9920b6e58";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [
  +        self."marshmallow"
  +      ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "UNKNOWN";
  +        license = licenses.mit;
  +        description = "Enum field for Marshmallow";
  +      };
  +    };
  +
  +    "more-babel-i18n" = python.mkDerivation {
  +      name = "more-babel-i18n-0.1.dev1";
  +      src = pkgs.fetchgit {
  +        url = "https://github.com/dpausp/more.babel_i18n";
  +        sha256 = "1w9ww3yi9f7fcf8lz0j65vq9x8lvsvans9ggpdr1snjancy9fx8v";
  +        rev = "c229b3048f994a716fc31b944172fb1800648f34";
  +      };
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [
  +        self."babel"
  +        self."jinja2"
  +        self."morepath"
  +      ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "UNKNOWN";
  +        license = licenses.bsdOriginal;
  +        description = "i18n/l10n support for morepath applications and Jinja2 templates";
  +      };
  +    };
  +
  +    "more-browser-session" = python.mkDerivation {
  +      name = "more-browser-session-0.1.dev1";
  +      src = pkgs.fetchgit {
  +        url = "https://github.com/dpausp/more.browser_session";
  +        sha256 = "0h15wdi35m1lgph476fvq48fy94xxjz233g8myv088nibvwiz25q";
  +        rev = "de3e96534d2fc605c6183f725fe2b42f6b410fa9";
  +      };
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [
  +        self."itsdangerous"
  +        self."morepath"
  +        self."werkzeug"
  +      ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "UNKNOWN";
  +        license = licenses.bsdOriginal;
  +        description = "HTTP Session support for Morepath applications";
  +      };
  +    };
  +
  +    "more-forwarded" = python.mkDerivation {
  +      name = "more-forwarded-0.2";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/7c/d8/e14f30346a9da2dc705f2206a04c70d40dc03e8238f3a9ac4bb668aedb25/more.forwarded-0.2.tar.gz";
  +        sha256 = "d6e89b4990dc98fe4476d1dea3c49506a3434d5fc8118d48afaeecfcaa0595c3";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [
  +        self."morepath"
  +      ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "http://pypi.python.org/pypi/more.static";
           license = licenses.bsdOriginal;
           description = "Forwarded header support for Morepath";
         };
       };
   
  -    "more.itsdangerous" = python.mkDerivation {
  -      name = "more.itsdangerous-0.0.2";
  -      src = pkgs.fetchurl { url = "https://files.pythonhosted.org/packages/56/22/a423e8d148b628cf62f8bc8ec63ffdbda62258783e68c743c987321e68f0/more.itsdangerous-0.0.2.tar.gz"; sha256 = "c0352ec418cb5f356261d88c600c18f7d7627895d357fe2f933fe643e42ba0f2"; };
  -      doCheck = commonDoCheck;
  -      checkPhase = "";
  -      installCheckPhase = "";
  -      buildInputs = commonBuildInputs;
  -      propagatedBuildInputs = [
  -      self."itsdangerous"
  -      self."morepath"
  -    ];
  -      meta = with pkgs.stdenv.lib; {
  -        homepage = "";
  +    "more-itsdangerous" = python.mkDerivation {
  +      name = "more-itsdangerous-0.0.2";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/56/22/a423e8d148b628cf62f8bc8ec63ffdbda62258783e68c743c987321e68f0/more.itsdangerous-0.0.2.tar.gz";
  +        sha256 = "c0352ec418cb5f356261d88c600c18f7d7627895d357fe2f933fe643e42ba0f2";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [
  +        self."itsdangerous"
  +        self."morepath"
  +      ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "http://github.com/morepath/more.itsdangerous";
           license = licenses.bsdOriginal;
           description = "An identity policy for morepath using itsdangerous.";
         };
       };
   
  -    "more.transaction" = python.mkDerivation {
  -      name = "more.transaction-0.9";
  -      src = pkgs.fetchurl { url = "https://files.pythonhosted.org/packages/16/fa/764e2a21bf42a3f15f07144548ae00503a982b94f81f845732e090ffd652/more.transaction-0.9.tar.gz"; sha256 = "b5ce7d11e6c71bb3b8b6eee060d25433e4ff7c377b5d42693d0be14a7a856ce6"; };
  -      doCheck = commonDoCheck;
  -      checkPhase = "";
  -      installCheckPhase = "";
  -      buildInputs = commonBuildInputs;
  -      propagatedBuildInputs = [
  -      self."morepath"
  -      self."transaction"
  -    ];
  -      meta = with pkgs.stdenv.lib; {
  -        homepage = "";
  +    "more-transaction" = python.mkDerivation {
  +      name = "more-transaction-0.9";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/16/fa/764e2a21bf42a3f15f07144548ae00503a982b94f81f845732e090ffd652/more.transaction-0.9.tar.gz";
  +        sha256 = "b5ce7d11e6c71bb3b8b6eee060d25433e4ff7c377b5d42693d0be14a7a856ce6";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [
  +        self."morepath"
  +        self."transaction"
  +      ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "https://github.com/morepath/more.transaction";
           license = licenses.bsdOriginal;
           description = "transaction integration for Morepath";
         };
       };
   
       "morepath" = python.mkDerivation {
  -      name = "morepath-0.18.1";
  -      src = pkgs.fetchurl { url = "https://files.pythonhosted.org/packages/99/d9/4b914c4552830546b4e84e9e9c53169eba142631493026a6a0813b564709/morepath-0.18.1.tar.gz"; sha256 = "4b634b52ad79e30cc31d10a5433dffd6105b4f37b45ee25c222b3a4ee67b21d7"; };
  -      doCheck = commonDoCheck;
  -      checkPhase = "";
  -      installCheckPhase = "";
  -      buildInputs = commonBuildInputs;
  -      propagatedBuildInputs = [
  -      self."WebOb"
  -      self."dectate"
  -      self."importscan"
  -      self."reg"
  -    ];
  -      meta = with pkgs.stdenv.lib; {
  -        homepage = "";
  +      name = "morepath-0.18.2";
  +      src = pkgs.fetchurl {
  +        url = "https://files.pythonhosted.org/packages/26/1c/fc413083ce6216dd459a46dea1273c57b98c2e657aeca40d5ff6487d5817/morepath-0.18.2.tar.gz";
  +        sha256 = "7bc289b0fe15aa74ad2faa33a6c8f3d4340395a2b8f09db1da9703d4a17bf346";
  +};
  +      doCheck = commonDoCheck;
  +      buildInputs = commonBuildInputs ++ [ ];
  +      propagatedBuildInputs = [
  +        self."dectate"
  +        self."importscan"
  +        self."reg"
  +        self."webob"
  +      ];
  +      meta = with pkgs.stdenv.lib; {
  +        homepage = "http://morepath.readthedocs.io";
           license = licenses.bsdOriginal;
           description = "A micro web-framework with superpowers";
         };
  
positive.code:       __old = pythonPackages;
        inherit interpreter;
        inherit interpreterWithPackages;
        mkDerivation = pythonPackages.buildPythonPackage;
        packages = pkgs;
        overrideDerivation = drv: f:
          pythonPackages.buildPythonPackage (
  
negative.code: # generated using pypi2nix tool (version: 2.0.0)
  # See more at: https://github.com/nix-community/pypi2nix
  #
  # COMMAND:
  #   pypi2nix -I nixpkgs=/home/ts/git/nixpkgs -V 3.7 -r pypi2nix_source_deps -E postgresql -E libffi
  #
  
  { pkgs ? import <nixpkgs> {},
  