diff --git a/posthog/clickhouse/test/test_schema.py b/posthog/clickhouse/test/test_schema.py
index c826086293e8d..f06d9884ed31e 100644
--- a/posthog/clickhouse/test/test_schema.py
+++ b/posthog/clickhouse/test/test_schema.py
@@ -13,7 +13,7 @@
 )
 
 
-def normalize_snapshots(built_query):
+def normalize_snapshots(built_query: str) -> str:
     # some zookeeper paths change on each run of a migration
     # can look for /clickhouse/tables/M0060_date_
     built_query = re.sub(