@spam_bot.on_chat_member_updated()
async def bot_join(client, message: Message):
@app.on_chat_member_updated()
async def on_chat_member_updated(client, chat_member_updated: ChatMemberUpdated):
if chat_member_updated.new_chat_member.user.is_self:
while True:
message = "Какое-то сообщение..."
await client.send_message(chat_member_updated.chat.id, message)
await asyncio.sleep(180)