python310Packages.mistune: add missing dependency (#382535)

pkgs/development/python-modules/mistune/default.nix

@@ -5,6 +5,7 @@
   pytestCheckHook,
   pythonOlder,
   setuptools,
+  typing-extensions,
 }:
 
 buildPythonPackage rec {
@@ -21,6 +22,10 @@ buildPythonPackage rec {
     hash = "sha256-gXCFBe58Ij6CiwTddsI4tkPsGBR2z9D8dnxlvTXGSMw=";
   };
 
+  dependencies = lib.optionals (pythonOlder "3.11") [
+    typing-extensions
+  ];
+
   build-system = [ setuptools ];
 
   nativeCheckInputs = [ pytestCheckHook ];