os.make_dirs is not a thing; os.makedirs is

We were also missing any coverage for this codepath :(

keras_hub/src/utils/preset_utils.py

@@ -240,7 +240,7 @@ def tf_copy_gfile_to_cache(preset, path):
         try:
             import tensorflow as tf
 
-            os.make_dirs(os.path.dirname(local_path), exist_ok=True)
+            os.makedirs(os.path.dirname(local_path), exist_ok=True)
             tf.io.gfile.copy(url, local_path)
         except Exception as e:
             # gfile.copy will leave an empty file after an error.

keras_hub/src/utils/preset_utils_test.py

@@ -33,6 +33,18 @@ def test_preset_errors(self):
         with self.assertRaisesRegex(ValueError, "class keras_hub>BortBackbone"):
             BertBackbone.from_preset(preset_dir)
 
+    @pytest.mark.large
+    def test_tf_file_io(self):
+        # Load a model from Kaggle to use as a test model.
+        preset = "bert_tiny_en_uncased"
+        backbone = BertBackbone.from_preset(preset)
+        # Save the model on a local directory.
+        temp_dir = self.get_temp_dir()
+        local_preset_dir = os.path.join(temp_dir, "bert_preset")
+        backbone.save_to_preset(local_preset_dir)
+        # Load with "file://" which tf supports.
+        backbone = BertBackbone.from_preset("file://" + local_preset_dir)
+
     @pytest.mark.large
     def test_upload_empty_preset(self):
         temp_dir = self.get_temp_dir()