anchor.diff:  
   
   
  -    "urllib3" = python.mkDerivation {
  -      name = "urllib3-1.22";
  -      src = pkgs.fetchurl { url = "https://pypi.python.org/packages/ee/11/7c59620aceedcc1ef65e156cc5ce5a24ef87be4107c2b74458464e437a5d/urllib3-1.22.tar.gz"; sha256 = "cc44da8e1145637334317feebd728bd869a35285b93cbb4cca2577da7e62db4f"; };
  -      doCheck = commonDoCheck;
  -      buildInputs = commonBuildInputs;
  -      propagatedBuildInputs = [
  -      self."certifi"
  -      self."idna"
  -    ];
  -      meta = with pkgs.stdenv.lib; {
  -        homepage = "https://urllib3.readthedocs.io/";
  -        license = licenses.mit;
  -        description = "HTTP library with thread-safe connection pooling, file post, and more.";
  -      };
  -    };
  -
  -
  -
       "validators" = python.mkDerivation {
         name = "validators-0.12.0";
         src = pkgs.fetchurl { url = "https://pypi.python.org/packages/8f/b5/9c9bf9cc9b50acea54a175eee97b0092f7676dbd6a17e00591588640acc3/validators-0.12.0.tar.gz"; sha256 = "bf1aa66554df0a7907f0e78b6d356e2ce30d6f2e73fefd1f3b14d20114341066"; };
  
positive.code:       doCheck = commonDoCheck;
        buildInputs = commonBuildInputs;
        propagatedBuildInputs = [
        self."SQLAlchemy"
        self."psycopg2"
        self."pytest"
        self."six"
      ];
        meta = with pkgs.stdenv.lib; {
  
negative.code:       src = pkgs.fetchurl { url = "https://pypi.python.org/packages/12/bc/595a77c4b5e204847fdf19268314ef59c85193a9dc9f83630fc459c0fee5/repoze.lru-0.7.tar.gz"; sha256 = "0429a75e19380e4ed50c0694e26ac8819b4ea7851ee1fc7583c8572db80aff77"; };
        doCheck = commonDoCheck;
        buildInputs = commonBuildInputs;
        propagatedBuildInputs = [ ];
        meta = with pkgs.stdenv.lib; {
          homepage = "http://www.repoze.org";
          license = "License :: Repoze Public License";
  