diff --git a/python-package/insightface/model_zoo/model_store.py b/python-package/insightface/model_zoo/model_store.py
index efa288c..87e0388 100644
--- a/python-package/insightface/model_zoo/model_store.py
+++ b/python-package/insightface/model_zoo/model_store.py
@@ -1,4 +1,7 @@
-"""Model store which provides pretrained models."""
+
+"""
+This code file mainly comes from https://github.com/dmlc/gluon-cv/blob/master/gluoncv/model_zoo/model_store.py
+"""
 from __future__ import print_function
 
 __all__ = ['get_model_file']
diff --git a/python-package/insightface/model_zoo/model_zoo.py b/python-package/insightface/model_zoo/model_zoo.py
index 3dd72a5..03b9801 100644
--- a/python-package/insightface/model_zoo/model_zoo.py
+++ b/python-package/insightface/model_zoo/model_zoo.py
@@ -1,6 +1,6 @@
 # pylint: disable=wildcard-import, unused-wildcard-import
-"""Model store which handles pretrained models from both
-mxnet.gluon.model_zoo.vision and gluoncv.models
+"""
+This code file mainly comes from https://github.com/dmlc/gluon-cv/blob/master/gluoncv/model_zoo/model_zoo.py
 """
 from .face_recognition import *
 from .face_detection import *
diff --git a/python-package/insightface/utils/download.py b/python-package/insightface/utils/download.py
index 98687e4..8f96fe6 100644
--- a/python-package/insightface/utils/download.py
+++ b/python-package/insightface/utils/download.py
@@ -1,4 +1,6 @@
-"""Download files with progress bar."""
+"""
+This code file mainly comes from https://github.com/dmlc/gluon-cv/blob/master/gluoncv/utils/download.py
+"""
 import os
 import hashlib
 import requests
diff --git a/python-package/insightface/utils/filesystem.py b/python-package/insightface/utils/filesystem.py
index a9273a9..4ecb091 100644
--- a/python-package/insightface/utils/filesystem.py
+++ b/python-package/insightface/utils/filesystem.py
@@ -1,4 +1,6 @@
-"""Filesystem utility functions."""
+"""
+This code file mainly comes from https://github.com/dmlc/gluon-cv/blob/master/gluoncv/utils/filesystem.py
+"""
 import os
 import errno