Support snapshot_download for ModelScope (#1194)

* add MLX_USE_MODELSCOPE env

* update

* update snapshot_download

* update

* remove modelscope dependency and add import check

* update

* nits

* fix

---------

Co-authored-by: wangxingjun778 <jason@U-C7X6TX5G-2239.local>
Co-authored-by: Awni Hannun <awni@apple.com>

llms/mlx_lm/utils.py

@@ -7,6 +7,7 @@ import glob
 import importlib
 import json
 import logging
+import os
 import shutil
 import time
 from dataclasses import dataclass
@@ -16,7 +17,17 @@ from typing import Any, Callable, Dict, Generator, List, Optional, Tuple, Type,
 
 import mlx.core as mx
 import mlx.nn as nn
+
+if os.getenv("MLXLM_USE_MODELSCOPE", "False").lower() == "true":
+    try:
+        from modelscope import snapshot_download
+    except ImportError:
+        raise ImportError(
+            "Please run `pip install modelscope` to activate the ModelScope."
+        )
+else:
     from huggingface_hub import snapshot_download
+
 from mlx.utils import tree_flatten, tree_reduce
 from transformers import PreTrainedTokenizer
 
@@ -154,11 +165,12 @@ def get_model_path(path_or_hf_repo: str, revision: Optional[str] = None) -> Path
         Path: The path to the model.
     """
     model_path = Path(path_or_hf_repo)
+
     if not model_path.exists():
         try:
             model_path = Path(
                 snapshot_download(
-                    repo_id=path_or_hf_repo,
+                    path_or_hf_repo,
                     revision=revision,
                     allow_patterns=[
                         "*.json",