1 files changed, 3 insertions, 3 deletions
diff --git a/tests/storage/test_redaction.py b/tests/storage/test_redaction.py
index dbacce4380..8c95a0a2fb 100644
--- a/tests/storage/test_redaction.py
+++ b/tests/storage/test_redaction.py
@@ -11,7 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from typing import Optional
+from typing import List, Optional
 
 from canonicaljson import json
 
@@ -234,8 +234,8 @@ class RedactionTestCase(unittest.HomeserverTestCase):
 
             async def build(
                 self,
-                prev_event_ids,
-                auth_event_ids,
+                prev_event_ids: List[str],
+                auth_event_ids: Optional[List[str]],
                 depth: Optional[int] = None,
             ):
                 built_event = await self._base_builder.build(