anchor.diff:  
   in stdenv.mkDerivation rec {
     pname = "pip";
  -  version = "9.0.1";
  +  version = "9.0.3";
     name = "${python.libPrefix}-bootstrapped-${pname}-${version}";
   
     src = fetchPypi {
       inherit pname version;
       format = "wheel";
  -    sha256 = "690b762c0a8460c303c089d5d0be034fb15a5ea2b75bdf565f40421f542fefb0";
  +    sha256 = "c3ede34530e0e0b2381e7363aded78e0c33291654937e7373032fda04e8803e5";
     };
   
     unpackPhase = ''
  
positive.code:     unzip -d $out/${python.sitePackages} $src
      unzip -d $out/${python.sitePackages} ${setuptools_source}
      unzip -d $out/${python.sitePackages} ${wheel_source}
      # TODO: Shouldn't be necessary anymore for pip > 9.0.1!
      cp ${pkg_resources} $out/${python.sitePackages}/pip/_vendor/pkg_resources/__init__.py
    '';
  
  
negative.code:   };
    setuptools_source = fetchPypi {
      pname = "setuptools";
      version = "39.0.1";
      format = "wheel";
      sha256 = "8010754433e3211b9cdbbf784b50f30e80bf40fc6b05eb5f865fab83300599b8";
    };
  
    # TODO: Shouldn't be necessary anymore for pip >= 10!
    # https://github.com/NixOS/nixpkgs/issues/26392
    # https://github.com/pypa/setuptools/issues/885
    pkg_resources = fetchurl {
  