openshadinglanguage: expose in python3Packages

It produces a Python module, so we want it to be here.

Once-upon-a-time someone told me `python3.pkgs` doesn’t work with
splicing or cross-compilation or something, so change that.

pkgs/by-name/op/openshadinglanguage/package.nix

@@ -13,7 +13,7 @@
   openimageio,
   partio,
   pugixml,
-  python3,
+  python3Packages,
   robin-map,
   stdenv,
   util-linux,
@@ -70,7 +70,7 @@ stdenv.mkDerivation (finalAttrs: {
     openimageio
     partio
     pugixml
-    python3.pkgs.pybind11
+    python3Packages.pybind11
     robin-map
     util-linux # needed just for hexdump
     zlib

pkgs/top-level/python-packages.nix

@@ -11448,6 +11448,10 @@ self: super: with self; {
 
   opensfm = callPackage ../development/python-modules/opensfm { };
 
+  openshadinglanguage = toPythonModule (
+    pkgs.openshadinglanguage.override { python3Packages = self; }
+  );
+
   openshift = callPackage ../development/python-modules/openshift { };
 
   opensimplex = callPackage ../development/python-modules/opensimplex { };