diff --git a/vn.strategy/strategydemo/strategyEngine.py b/vn.strategy/strategydemo/strategyEngine.py
index 692444c0..35a50f5c 100644
--- a/vn.strategy/strategydemo/strategyEngine.py
+++ b/vn.strategy/strategydemo/strategyEngine.py
@@ -1081,6 +1081,7 @@ class StrategyTemplate(object):
                 return ref
         else:
             return None
+        
         print (u'strategyEngine.py cover() end.')
 
     #----------------------------------------------------------------------