add llamafy_qwen.py

src/llmtuner/tuner/core/loader.py

@@ -128,7 +128,7 @@ def load_model_and_tokenizer(
         else:
             logger.warning("Current model does not support RoPE scaling.")
 
-    # Set FlashAttention-2
+    # Set FlashAttention-2 and S^2-Attn
     if model_args.flash_attn:
         if getattr(config, "model_type", None) == "llama":
             LlamaModule.LlamaAttention = LlamaPatches.LlamaFlashAttention2