anchor.diff:  , pathlib2
   , virtualenv
   , functools32
  +, clikit
  +, keyring
  +, pexpect
  +, importlib-metadata
   , pytest
   , jsonschema
  +, intreehooks
  +, lockfile
   }:
   
   let
  -  cleo6 = cleo.overridePythonAttrs (oldAttrs: rec {
  -    version = "0.6.8";
  -    src = fetchPypi {
  -      inherit (oldAttrs) pname;
  -      inherit version;
  -      sha256 = "06zp695hq835rkaq6irr1ds1dp2qfzyf32v60vxpd8rcnxv319l5";
  -    };
  -  });
     glob2 = callPackage ./glob2.nix { };
   
   in buildPythonPackage rec {
     pname = "poetry";
  -  version = "0.12.17";
  +  version = "1.0.3";
   
     src = fetchPypi {
       inherit pname version;
  -    sha256 = "0gxwcd65qjmzqzppf53x51sic1rbcd9py6cdzx3aprppipimslvf";
  +    sha256 = "0fx1ilgkrsqjjnpgv5zljsp0wpcsywdqvvi8im9z396qq6qpk830";
     };
   
     postPatch = ''
  -    substituteInPlace setup.py --replace \
  -      "requests-toolbelt>=0.8.0,<0.9.0" \
  -      "requests-toolbelt>=0.8.0,<0.10.0" \
  -      --replace 'pyrsistent>=0.14.2,<0.15.0' 'pyrsistent>=0.14.2,<0.16.0'
  +    substituteInPlace pyproject.toml \
  +     --replace "pyrsistent = \"^0.14.2\"" "pyrsistent = \"^0.15.0\"" \
  +     --replace "requests-toolbelt = \"^0.8.0\"" "requests-toolbelt = \"^0.9.0\"" \
  +     --replace "importlib-metadata = {version = \"~1.1.3\", python = \"<3.8\"}" \
  +       "importlib-metadata = {version = \"~1.3.0\", python = \"<3.8\"}"
     '';
   
     format = "pyproject";
   
  +  nativeBuildInputs = [ intreehooks ];
  +
     propagatedBuildInputs = [
  -    cachy
  -    cleo6
  +    cleo
  +    clikit
       requests
       cachy
       requests-toolbelt
  
positive.code:   '';
  
    meta = with lib; {
      homepage = https://github.com/sdispater/poetry;
      description = "Python dependency management and packaging made easy";
      license = licenses.mit;
      maintainers = with maintainers; [ jakewaksbaum ];
  
negative.code: { lib, buildPythonPackage, fetchPypi, callPackage
  , isPy27, isPy34, pythonOlder
  , cleo
  , requests
  , cachy
  