anchor.diff: -{ lib, buildPythonPackage, fetchFromGitHub, pythonOlder, black, isort
  -, pytestCheckHook, pyyaml, typing-extensions, typing-inspect, dataclasses }:
  +{ lib
  +, buildPythonPackage
  +, fetchFromGitHub
  +, pythonOlder
  +, hypothesis
  +, doCheck ? true
  +, dataclasses
  +, hypothesmith
  +, pytestCheckHook
  +, pyyaml
  +, typing-extensions
  +, typing-inspect
  +, black
  +, isort
  +}:
   
   buildPythonPackage rec {
     pname = "libcst";
  -  version = "0.3.13";
  +  version = "0.3.17";
   
     # Some files for tests missing from PyPi
     # https://github.com/Instagram/LibCST/issues/331
  
positive.code:       "A Concrete Syntax Tree (CST) parser and serializer library for Python.";
      homepage = "https://github.com/Instagram/libcst";
      license = with licenses; [ mit asl20 psfl ];
      maintainers = with maintainers; [ maintainers.ruuda ];
    };
  }
  
negative.code:     owner = "instagram";
      repo = pname;
      rev = "v${version}";
      sha256 = "sha256-mlSeB9OjCiUVYwcPYNrQdlfcj9DV/+wqVWt91uFsQsU=";
    };
  
    disabled = pythonOlder "3.6";
  
    propagatedBuildInputs = [ hypothesis typing-inspect pyyaml ]
      ++ lib.optional (pythonOlder "3.7") dataclasses;
  
    checkInputs = [ black hypothesmith isort pytestCheckHook ];
  
    inherit doCheck;
  
    preCheck = ''
      python -m libcst.codegen.generate visitors
      python -m libcst.codegen.generate return_types
    '';
  
    pythonImportsCheck = [ "libcst" ];
  