Base handler is generic abstract class and should be used in all other class-based handlers.
from aiogram.handler import BaseHandler
By default you will need to override only method
async def handle(self) -> Any: ...
This class is also have an default initializer and you don’t need to change it.
Initializer accepts current event and all contextual data and which
can be accessed from the handler through attributes:
event: TelegramEvent and
data: Dict[Any, str]
If instance of the bot is specified in context data or current context it can be accessed through bot class attribute.
class MyHandler(BaseHandler[Message]): async def handle(self) -> Any: await self.event.answer("Hello!")