diff --git a/heat/engine/update.py b/heat/engine/update.py
index 5f0d2e0d34..85cf62fb2c 100644
--- a/heat/engine/update.py
+++ b/heat/engine/update.py
@@ -34,7 +34,7 @@ class StackUpdate(object):
         self.existing_snippets = dict((r.name, r.parsed_template())
                                       for r in self.existing_stack)
 
-    def __str__(self):
+    def __repr__(self):
         return '%s Update' % str(self.existing_stack)
 
     @scheduler.wrappertask