use @dataclass instead of custom constructor

Author: mhils

src/h2/events.py

@@ -11,6 +11,7 @@
 from __future__ import annotations
 
 import binascii
+from dataclasses import dataclass
 from typing import TYPE_CHECKING
 
 from .settings import ChangedSetting, SettingCodes, Settings, _setting_code_from_int
@@ -292,6 +293,7 @@ def __repr__(self) -> str:
         )
 
 
+@dataclass(kw_only=True)
 class WindowUpdated(Event):
     """
     The WindowUpdated event is fired whenever a flow control window changes
@@ -307,15 +309,11 @@ class WindowUpdated(Event):
     May be ``0`` if the connection window was changed.
     """
 
-    delta: int | None
+    delta: int | None = None
     """
     The window delta.
     """
 
-    def __init__(self, *, stream_id: int, delta: int | None = None) -> None:
-        self.stream_id = stream_id
-        self.delta = delta
-
     def __repr__(self) -> str:
         return f"<WindowUpdated stream_id:{self.stream_id}, delta:{self.delta}>"