diff --git a/01.fit_a_line/train.py b/01.fit_a_line/train.py
index 0d567fef5974e845fcfb0ec036c0df5cb60741ef..dcae9ac51ce529da5b59b0d34e997c3b2a5d6716 100644
--- a/01.fit_a_line/train.py
+++ b/01.fit_a_line/train.py
@@ -14,11 +14,13 @@
 
 from __future__ import print_function
 
+import sys
+
+import math
+import numpy
+
 import paddle
 import paddle.fluid as fluid
-import numpy
-import math
-import sys
 
 
 # For training test cost