diff --git a/scenarionet/builder/utils.py b/scenarionet/builder/utils.py
index 9a38095..93f4521 100644
--- a/scenarionet/builder/utils.py
+++ b/scenarionet/builder/utils.py
@@ -52,7 +52,7 @@ def combine_multiple_dataset(output_path, *dataset_paths,
     :param try_generate_missing_file: If dataset_summary.pkl and mapping.pkl are missing, whether to try generating them
     :param dataset_paths: Path of each dataset
     :param filters: a set of filters to choose which scenario to be selected and added into this combined dataset
-    :return:
+    :return: summary, mapping
     """
     filters = filters or []
     output_abs_path = osp.abspath(output_path)
diff --git a/scenarionet/tests/test_combine_dataset.py b/scenarionet/tests/test_combine_dataset.py
index 25d2157..ffabed4 100644
--- a/scenarionet/tests/test_combine_dataset.py
+++ b/scenarionet/tests/test_combine_dataset.py
@@ -8,7 +8,7 @@ from scenarionet.verifier.utils import verify_loading_into_metadrive
 
 def test_combine_multiple_dataset():
     dataset_name = "nuscenes"
-    original_dataset_path = os.path.join(SCENARIONET_PACKAGE_PATH, "tests", "_test_dataset", dataset_name)
+    original_dataset_path = os.path.join(SCENARIONET_PACKAGE_PATH, "tests", "test_dataset", dataset_name)
     dataset_paths = [original_dataset_path + "_{}".format(i) for i in range(5)]
 
     output_path = os.path.join(SCENARIONET_PACKAGE_PATH, "tests", "combine")
@@ -22,7 +22,7 @@ def test_combine_multiple_dataset():
         for scenario_file in sorted_scenarios:
             read_scenario(os.path.join(dataset_path, mapping[scenario_file], scenario_file))
         success, result = verify_loading_into_metadrive(dataset_path,
-                                                        result_save_dir="_test_dataset",
+                                                        result_save_dir="test_dataset",
                                                         steps_to_run=300)
         assert success
 
diff --git a/scenarionet/tests/test_filter.py b/scenarionet/tests/test_filter.py
index 96ba438..bf4bc28 100644
--- a/scenarionet/tests/test_filter.py
+++ b/scenarionet/tests/test_filter.py
@@ -9,7 +9,7 @@ from metadrive.type import MetaDriveType
 
 def test_filter_dataset():
     dataset_name = "nuscenes"
-    original_dataset_path = os.path.join(SCENARIONET_PACKAGE_PATH, "tests", "_test_dataset", dataset_name)
+    original_dataset_path = os.path.join(SCENARIONET_PACKAGE_PATH, "tests", "test_dataset", dataset_name)
     dataset_paths = [original_dataset_path + "_{}".format(i) for i in range(5)]
 
     output_path = os.path.join(SCENARIONET_PACKAGE_PATH, "tests", "combine")