Marginally improve some 'Aggregator' code and docs.

declearn/aggregator/_api.py

@@ -18,7 +18,7 @@
 """Model updates aggregation API."""
 
 from abc import ABCMeta, abstractmethod
-from typing import Any, ClassVar, Dict
+from typing import Any, ClassVar, Dict, TypeVar
 
 from typing_extensions import Self  # future: import from typing (py >=3.11)
 
@@ -30,6 +30,9 @@ __all__ = [
 ]
 
 
+T = TypeVar("T")
+
+
 @create_types_registry
 class Aggregator(metaclass=ABCMeta):
     """Abstract class defining an API for Vector aggregation.
@@ -90,9 +93,9 @@ class Aggregator(metaclass=ABCMeta):
     @abstractmethod
     def aggregate(
         self,
-        updates: Dict[str, Vector],
+        updates: Dict[str, Vector[T]],
         n_steps: Dict[str, int],  # revise: abstract~generalize kwargs use
-    ) -> Vector:
+    ) -> Vector[T]:
         """Aggregate input vectors into a single one.
 
         Parameters
@@ -109,6 +112,11 @@ class Aggregator(metaclass=ABCMeta):
         gradients: Vector
             Aggregated updates, as a Vector - treated as gradients by
             the server-side optimizer.
+
+        Raises
+        ------
+        TypeError
+            If the input `updates` are an empty dict.
         """
 
     def get_config(

declearn/aggregator/_base.py

@@ -19,7 +19,6 @@
 
 from typing import Any, ClassVar, Dict, Optional
 
-from typing_extensions import Self  # future: import from typing (py >=3.11)
 
 from declearn.aggregator._api import Aggregator
 from declearn.model.api import Vector
@@ -76,13 +75,6 @@ class AveragingAggregator(Aggregator):
             "client_weights": self.client_weights,
         }
 
-    @classmethod
-    def from_config(
-        cls,
-        config: Dict[str, Any],
-    ) -> Self:
-        return cls(**config)
-
     def aggregate(
         self,
         updates: Dict[str, Vector],