1 files changed, 1 insertions, 1 deletions
diff --git a/synapse/rest/admin/users.py b/synapse/rest/admin/users.py
index c1a1ba645e..681e491826 100644
--- a/synapse/rest/admin/users.py
+++ b/synapse/rest/admin/users.py
@@ -419,7 +419,7 @@ class UserRegisterServlet(RestServlet):
         self.nonces: Dict[str, int] = {}
         self.hs = hs
 
-    def _clear_old_nonces(self):
+    def _clear_old_nonces(self) -> None:
         """
         Clear out old nonces that are older than NONCE_TIMEOUT.
         """