1 files changed, 2 insertions, 2 deletions
diff --git a/synapse/types.py b/synapse/types.py
index 8d2fa00f71..64c442bd0f 100644
--- a/synapse/types.py
+++ b/synapse/types.py
@@ -182,14 +182,14 @@ def create_requester(
     )
 
 
-def get_domain_from_id(string):
+def get_domain_from_id(string: str) -> str:
     idx = string.find(":")
     if idx == -1:
         raise SynapseError(400, "Invalid ID: %r" % (string,))
     return string[idx + 1 :]
 
 
-def get_localpart_from_id(string):
+def get_localpart_from_id(string: str) -> str:
     idx = string.find(":")
     if idx == -1:
         raise SynapseError(400, "Invalid ID: %r" % (string,))