Minor

cacheflow/worker/cache_engine.py

@@ -20,7 +20,8 @@ class CacheEngine:
         dtype: torch.dtype,
     ) -> None:
         if head_size % 16 != 0:
-            raise ValueError(f'head_size ({head_size}) must be a multiple of 16.')
+            raise ValueError(
+                f'head_size ({head_size}) must be a multiple of 16.')
 
         self.worker_id = worker_id
         self.gpu_id = gpu_id
@@ -40,7 +41,7 @@ class CacheEngine:
         self.cache_stream = torch.cuda.Stream(device=gpu_id)
         assert self.cache_stream != torch.cuda.current_stream(device=gpu_id)
         # Initialize the events for stream synchronization.
-        self.events = [torch.cuda.Event() for _ in range(self.num_layers)]
+        self.events = [torch.cuda.Event() for _ in range(num_layers)]
 
     def get_key_block_shape(self) -> Tuple[int, int, int, int]:
         element_size = torch.tensor([], dtype=self.dtype).element_size()