chore: fix shutdown error when not install torch

pilot/model/loader.py

@@ -18,6 +18,7 @@ from pilot.logs import logger
 def _check_multi_gpu_or_4bit_quantization(model_params: ModelParameters):
     # TODO: vicuna-v1.5 8-bit quantization info is slow
     # TODO: support wizardlm quantization, see: https://huggingface.co/WizardLM/WizardLM-13B-V1.2/discussions/5
+    # TODO: support internlm quantization
     model_name = model_params.model_name.lower()
     supported_models = ["llama", "baichuan", "vicuna"]
     return any(m in model_name for m in supported_models)

pilot/utils/model_utils.py

@@ -2,10 +2,12 @@ import logging
 
 
 def _clear_torch_cache(device="cuda"):
+    try:
+        import torch
+    except ImportError:
+        return
     import gc
 
-    import torch
-
     gc.collect()
     if device != "cpu":
         if torch.has_mps: