Raise an error when using deprecated property

PiperOrigin-RevId: 868099334

Author: Conchylicultor

kauldron/utils/sharding_utils.py

@@ -105,7 +105,9 @@ def set_global_mesh(self) -> Iterator[None]:
   @property
   def ds(self):
     """DEPRECATED: Use `batch` instead."""
-    return self.batch
+    raise DeprecationWarning(
+        '`sharding.ds` is deprecated. Use `sharding.batch` instead.'
+    )
 
 
 @dataclasses.dataclass(frozen=True, kw_only=True)