Update modules/memory_updater.py

modules/memory_updater.py

@@ -23,7 +23,8 @@ class SequenceMemoryUpdater(MemoryUpdater):
                                                                                      "update memory to time in the past"
 
     memory = self.memory.get_memory(unique_node_ids)
-    self.memory.last_update[unique_node_ids] = timestamps
+    with torch.no_grad():
+        self.memory.last_update[unique_node_ids] = timestamps
 
     updated_memory = self.memory_updater(unique_messages, memory)