Issues with asynchronously handling a Subscriber callback

Question

I am trying to create a listener that sends a message through a Discord webhook to my Discord server. The issue that I am encountering at the moment is that I do not know how to create an asynchronous task in a synchronous callback (since according to the internet, an asynchronous callback does not exist).

task = self.event_loop.create_task(self._createLog(data)) stacks and is executed AFTER I initially terminate the Python program, and not while this callback is running. What do I do incorrectly here, and are there any other methods that are better practice to achieve this? Thanks in advance.

#!/usr/bin/env python3
import rospy
from std_msgs.msg import String
import asyncio
from discord_webhook import AsyncDiscordWebhook
from discord_webhook import DiscordEmbed


class listenerHandler:
    def _init_(self, discord_whurl: str, ros_node_name: str ,ros_topic: str):
        rospy.init_node(ros_node_name)

        self._last_post_unix = 0

        self._whurl = discord_whurl
        self._rt = ros_topic
        self._event_loop = asyncio.get_running_loop()
        print(self._event_loop)


    @property
    def webhook_url(self):
        return self._whurl
    
    @webhook_url.setter
    def webhook_url(self, url: str):
        self._whurl = url


    async def __sendLog(self, log: dict) -> None:
        print(log,' sending')
        self._embed = DiscordEmbed(title=log['title'], description=log['descripiton'], color="6dc5ff")

        self._webhook = AsyncDiscordWebhook(url=self._whurl)
        self._webhook.add_embed(self._embed)

        await self._webhook.execute()
        self._last_post_unix = rospy.get_time()

    async def __createLog(self, data) -> None:
        rospy.loginfo('creating log')
        log = {'title': self._rt, 'description': data.data}

        await self.__sendLog(log)


    def __callback(self, data):
        if rospy.get_time() - self._last_post_unix > 5:
            self._last_post_unix = rospy.get_time()
            print(rospy.get_time(), self._last_post_unix)
            rospy.loginfo('running loop')
            
            task = self.event_loop.create_task(self._createLog(data))

    def activate_listener(self):
        rospy.Subscriber(self._rt, String, self.__callback)

    async def async_spin(self):
        rospy.loginfo("beginning node spin")

        while not rospy.is_shutdown():
            pass


async def main():
    lh = listenerHandler(discord_whurl='https://discord.com/api/webhooks/1158359060140265503/deUeh_5dXFbmeoNeKwnRtWAMMnM7mI_4LtyXRtkpabYSq3oHGtzjY6rbJn9oT45QNXZV', ros_node_name='R_toDiscord_node' ,ros_topic='topic_1')
    lh.activate_listener()

    await lh.async_spin()

if _name_ == '_main_':
    asyncio.run(main())
```