Improve conversation typing (#136084)

homeassistant/components/conversation/session.py

@@ -1,11 +1,13 @@
 """Conversation history."""
 
+from __future__ import annotations
+
 from collections.abc import AsyncGenerator
 from contextlib import asynccontextmanager
 from dataclasses import dataclass, field, replace
 from datetime import datetime, timedelta
 import logging
-from typing import Generic, Literal, TypeVar
+from typing import Literal
 
 from homeassistant.const import EVENT_HOMEASSISTANT_STOP
 from homeassistant.core import (
@@ -25,16 +27,15 @@ from homeassistant.util.hass_dict import HassKey
 from .const import DOMAIN
 from .models import ConversationInput, ConversationResult
 
-DATA_CHAT_HISTORY: HassKey["dict[str, ChatSession]"] = HassKey(
+DATA_CHAT_HISTORY: HassKey[dict[str, ChatSession]] = HassKey(
     "conversation_chat_session"
 )
-DATA_CHAT_HISTORY_CLEANUP: HassKey["SessionCleanup"] = HassKey(
+DATA_CHAT_HISTORY_CLEANUP: HassKey[SessionCleanup] = HassKey(
     "conversation_chat_session_cleanup"
 )
 
 LOGGER = logging.getLogger(__name__)
 CONVERSATION_TIMEOUT = timedelta(minutes=5)
-_NativeT = TypeVar("_NativeT")
 
 
 class SessionCleanup:
@@ -89,7 +90,7 @@ class SessionCleanup:
 async def async_get_chat_session(
     hass: HomeAssistant,
     user_input: ConversationInput,
-) -> AsyncGenerator["ChatSession"]:
+) -> AsyncGenerator[ChatSession]:
     """Return chat session."""
     all_history = hass.data.get(DATA_CHAT_HISTORY)
     if all_history is None:
@@ -164,7 +165,7 @@ class ConverseError(HomeAssistantError):
 
 
 @dataclass
-class ChatMessage(Generic[_NativeT]):
+class ChatMessage[_NativeT]:
     """Base class for chat messages.
 
     When role is native, the content is to be ignored and message
@@ -184,7 +185,7 @@ class ChatMessage(Generic[_NativeT]):
 
 
 @dataclass
-class ChatSession(Generic[_NativeT]):
+class ChatSession[_NativeT]:
     """Class holding all information for a specific conversation."""
 
     hass: HomeAssistant