pythonPackages.pysideShiboken: fix build with python 3.9

pkgs/development/python-modules/pyside/shiboken.nix

@@ -1,8 +1,6 @@
 { lib, fetchFromGitHub, buildPythonPackage
 , cmake
-, isPy35
-, isPy36
-, isPy37
+, fetchurl
 , isPy3k
 , libxml2
 , libxslt
@@ -10,6 +8,7 @@
 , pysideApiextractor
 , pysideGeneratorrunner
 , python
+, pythonAtLeast
 , qt4
 , sphinx
 }:
@@ -39,8 +38,17 @@ buildPythonPackage rec {
       \"$\{GENERATORRUNNER_PLUGIN_DIR}\" lib/generatorrunner/
   '';
 
-  # gcc6 patch was also sent upstream: https://github.com/pyside/Shiboken/pull/86
-  patches = [ ./gcc6.patch ] ++ (lib.optional (isPy35 || isPy36 || isPy37) ./shiboken_py35.patch);
+  patches = [
+    # gcc6 patch was also sent upstream: https://github.com/pyside/Shiboken/pull/86
+    ./gcc6.patch
+    (lib.optional (pythonAtLeast "3.5") ./shiboken_py35.patch)
+    (fetchurl {
+      # https://github.com/pyside/Shiboken/pull/90
+      name = "fix-build-with-python-3.9.patch";
+      url = "https://github.com/pyside/Shiboken/commit/d1c901d4c0af581003553865360ba964cda041e8.patch";
+      sha256 = "1f7slz8n8rps5r67hz3hi4rr82igc3l166shfy6647ivsb2fnxwy";
+    })
+  ];
 
   cmakeFlags = lib.optionals isPy3k [
     "-DUSE_PYTHON3=TRUE"