[Core] Refactor model loading code (#4097)

examples/tensorize_vllm_model.py

@@ -16,8 +16,8 @@ from transformers import AutoConfig, PretrainedConfig
 from vllm.distributed import initialize_model_parallel
 from vllm.engine.arg_utils import EngineArgs
 from vllm.engine.llm_engine import LLMEngine
+from vllm.model_executor.model_loader.tensorizer import TensorizerArgs
 from vllm.model_executor.models import ModelRegistry
-from vllm.model_executor.tensorizer_loader import TensorizerArgs
 
 # yapf conflicts with isort for this docstring
 # yapf: disable