Use auto_attribs/native type hints for attrs classes. (#11692)

1 files changed, 3 insertions, 3 deletions

diff --git a/synapse/storage/databases/main/roommember.py b/synapse/storage/databases/main/roommember.py
index cda80d6511..4489732fda 100644
--- a/synapse/storage/databases/main/roommember.py
+++ b/synapse/storage/databases/main/roommember.py
@@ -1177,18 +1177,18 @@ class RoomMemberStore(RoomMemberWorkerStore, RoomMemberBackgroundUpdateStore):
         await self.db_pool.runInteraction("forget_membership", f)
 
 
-@attr.s(slots=True)
+@attr.s(slots=True, auto_attribs=True)
 class _JoinedHostsCache:
     """The cached data used by the `_get_joined_hosts_cache`."""
 
     # Dict of host to the set of their users in the room at the state group.
-    hosts_to_joined_users = attr.ib(type=Dict[str, Set[str]], factory=dict)
+    hosts_to_joined_users: Dict[str, Set[str]] = attr.Factory(dict)
 
     # The state group `hosts_to_joined_users` is derived from. Will be an object
     # if the instance is newly created or if the state is not based on a state
     # group. (An object is used as a sentinel value to ensure that it never is
     # equal to anything else).
-    state_group = attr.ib(type=Union[object, int], factory=object)
+    state_group: Union[object, int] = attr.Factory(object)
 
     def __len__(self):
         return sum(len(v) for v in self.hosts_to_joined_users.values())