diff --git a/visualdl/python/test_storage.py b/visualdl/python/test_storage.py
index 413ac306ce09fd4adfae5e3a751ae5e545ad9c73..328ee74efdacd4c429055ef0eff2d218360ba401 100644
--- a/visualdl/python/test_storage.py
+++ b/visualdl/python/test_storage.py
@@ -4,13 +4,15 @@ import unittest
 import random
 import time
 
+
 class StorageTest(unittest.TestCase):
     def setUp(self):
         self.dir = "./tmp/storage_test"
 
     def test_read(self):
         print 'test write'
-        self.writer = storage.StorageWriter(self.dir, sync_cycle=1).as_mode("train")
+        self.writer = storage.StorageWriter(
+            self.dir, sync_cycle=1).as_mode("train")
         scalar = self.writer.scalar("model/scalar/min")
         # scalar.set_caption("model/scalar/min")
         for i in range(10):