fix types

Author: dcherian

flox/aggregations.py

@@ -162,8 +162,8 @@ def __init__(
         self,
         name: str,
         *,
-        numpy: str | None = None,
-        chunk: str | FuncTuple | None,
+        numpy: partial | str | None = None,
+        chunk: partial | str | FuncTuple | None,
         combine: str | FuncTuple | None,
         preprocess: Callable | None = None,
         finalize: Callable | None = None,