Specify the `None` return type of `ReleaseManager.release`
@@ -25,7 +25,7 @@ class ReleaseManager(metaclass=abc.ABCMeta):
"""
@abc.abstractmethod
- async def release(self, value: Any, key: Any = None):
+ async def release(self, value: Any, key: Any = None) -> None:
"""Releases `value` from a federated program.
An implementation of this interface should be specific about the types of
