{ lib , fetchFromGitHub , buildPythonPackage , typing , python , pythonOlder }: buildPythonPackage rec { pname = "mypy-extensions"; version = "0.4.3"; src = fetchFromGitHub { owner = "python"; repo = "mypy_extensions"; rev = version; sha256 = "sha256-JjhbxX5DBAbcs1o2fSWywz9tot792q491POXiId+NyI="; }; propagatedBuildInputs = lib.optional (pythonOlder "3.5") typing; checkPhase = '' ${python.interpreter} -m unittest discover tests ''; pythonImportsCheck = [ "mypy_extensions" ]; meta = with lib; { description = "Experimental type system extensions for programs checked with the mypy typechecker"; homepage = "http://www.mypy-lang.org"; license = licenses.mit; maintainers = with maintainers; [ martingms lnl7 SuperSandro2000 ]; }; }