diff --git a/rhodecode/integrations/types/handlers/slack.py b/rhodecode/integrations/types/handlers/slack.py
--- a/rhodecode/integrations/types/handlers/slack.py
+++ b/rhodecode/integrations/types/handlers/slack.py
@@ -19,7 +19,6 @@ import re
 import textwrap
 import dataclasses
 import logging
-import typing
 
 from mako.template import Template
 
@@ -66,7 +65,7 @@ class SlackDataHandler(CommitParsingData
     def __init__(self):
         pass
 
-    def __call__(self, event: events.RhodecodeEvent, data):
+    def __call__(self, event: events.RhodecodeEvent, data) -> SlackData:
         if not isinstance(event, events.RhodecodeEvent):
             raise TypeError(f"event {event} is not subtype of events.RhodecodeEvent")