Fix unrelated change

Signed-off-by: Balaji Veeramani <[email protected]>

python/ray/experimental/channel/shared_memory_channel.py

@@ -6,8 +6,7 @@
 
 import ray
 import ray.exceptions
-
-# from ray._raylet import SerializedObject
+from ray._raylet import SerializedObject
 from ray.experimental.channel import utils
 from ray.experimental.channel.common import ChannelInterface, ChannelOutputType
 from ray.experimental.channel.intra_process_channel import IntraProcessChannel
@@ -774,4 +773,3 @@ def _resolve_actor_id(self) -> str:
     def close(self) -> None:
         for channel in self._channels:
             channel.close()
-            channel.close()