diff --git a/docs/source/error_code_list.rst b/docs/source/error_code_list.rst
index 324aad93ecae..2842d941f5c5 100644
--- a/docs/source/error_code_list.rst
+++ b/docs/source/error_code_list.rst
@@ -1173,7 +1173,7 @@ Example:
         ...
 
     def process(response1,response2)-> Union[object,int]:
-    return response1 + response2
+        return response1 + response2
 
 .. _code-annotation-unchecked: