diff --git a/contrib/plugins/addrelease.py b/contrib/plugins/addrelease.py
index bff38cf38..b7a0db1c0 100644
--- a/contrib/plugins/addrelease.py
+++ b/contrib/plugins/addrelease.py
@@ -95,7 +95,7 @@ class AddObjectAsEntity(BaseAction):
                 html_file = self.generate_html_file(self.form_values)
                 self.open_html_file(html_file)
         finally:
-            self.form_values.clear
+            self.form_values.clear()
 
 
 class AddClusterAsRelease(AddObjectAsEntity):