How to use the asgiref.sync.AsyncToSync function in asgiref

def send_message(self, message):
        if not self.chat:
            AsyncToSync(self.send_json)(
                {
                    'error': 'NO_CHAT_JOINED'
                }
            )
        else:
            try:
                blacklist_validator(message)
                Messages.objects.send_message(sender=self.scope['user'], receiver_id=self.chat, message=message)
            except ValidationError:
                AsyncToSync(self.send_json)(
                    {
                        'error': 'BLACKLISTED_MESSAGE'
                    }

Returns None if there is no task.
        """
        try:
            if hasattr(asyncio, "current_task"):
                # Python 3.7 and up
                return asyncio.current_task()
            else:
                # Python 3.6
                return asyncio.Task.current_task()
        except RuntimeError:
            return None


# Lowercase is more sensible for most things
sync_to_async = SyncToAsync
async_to_sync = AsyncToSync

def send_message(self, message):
        if not self.chat:
            AsyncToSync(self.send_json)(
                {
                    'error': 'NO_CHAT_JOINED'
                }
            )
        else:
            try:
                blacklist_validator(message)
                Messages.objects.send_message(sender=self.scope['user'], receiver_id=self.chat, message=message)
            except ValidationError:
                AsyncToSync(self.send_json)(
                    {
                        'error': 'BLACKLISTED_MESSAGE'
                    }

async def __call__(self, scope, receive, send):
        if scope["type"] != "http":
            raise ValueError("WSGI wrapper received a non-HTTP scope")
        self.scope = scope
        with SpooledTemporaryFile(max_size=65536) as body:
            # Alright, wait for the http.request messages
            while True:
                message = await receive()
                if message["type"] != "http.request":
                    raise ValueError("WSGI wrapper received a non-HTTP-request message")
                body.write(message.get("body", b""))
                if not message.get("more_body"):
                    break
            body.seek(0)
            # Wrap send so it can be called from the subthread
            self.sync_send = AsyncToSync(send)
            # Call the WSGI app
            await self.run_wsgi_app(body)