How to create instance of class during django startup

I am developing MQTT dashboard application with django. I have a table in database which contains list of devices, and one of its parameters is poll_interval_ms. I want to create MqttChannel object (class I created for mqtt connection with devices) for every device which has poll_interval greater than 0.

What I already learned is that any startup operations should be placed in ready method in class ApplicationConfig. So I am thinking about something like this:

class DashboardConfig(AppConfig):
    name = 'dashboard'
    client_list = []

    def ready(self):
        from .models import Device
        devices_set = Device.objects.all()
        for device in devices_set:
            if device.poll_interval_ms > 0:
                client = MqttChannel(device.id, is_server=True)
                self.client_list.append(client)

Now my question is how to do it properly to access client_list later in code? Should I leave it as it is and access it as dashboard.apps.DashboardConfig.client_list (I'm not even sure if this will work) or is there some better way to do it?