chore: import upstream snapshot with attribution

python/ray/util/joblib/__init__.py

@@ -0,0 +1,20 @@
+from joblib.parallel import register_parallel_backend
+
+
+def register_ray():
+    """Register Ray Backend to be called with parallel_backend("ray")."""
+    try:
+        from ray.util.joblib.ray_backend import RayBackend
+
+        register_parallel_backend("ray", RayBackend)
+    except ImportError:
+        msg = (
+            "To use the ray backend you must install ray."
+            "Try running 'pip install ray'."
+            "See https://docs.ray.io/en/master/installation.html"
+            "for more information."
+        )
+        raise ImportError(msg)
+
+
+__all__ = ["register_ray"]