Connecting to MQTT and expiring component

I’m trying to run this script in a python script to simulate a robot:

Run the following code in VS CODE

import paho.mqtt.client as mqtt
import time

broker = "mqtt.eclipseprojects.io"
port = 1883
topic = "robot/signal"

client = mqtt.Client()
client.connect(broker, port, 60)
client.loop_start()

message_count = 0
try:
    while True:
        payload = f"Simulated message {message_count}"
        client.publish(topic, payload)
        print(f"Published: {payload}")
        message_count += 1
        time.sleep(1)
except KeyboardInterrupt:
    client.loop_stop()
    client.disconnect()

Now I woujld like to listen to this in Grasshopper and expire a pytho ncomponent everytime it fires.

For this I use this code.

import paho.mqtt.client as mqtt
import Rhino
import Grasshopper

class MyComponent(Grasshopper.Kernel.GH_ScriptInstance):
    def __init__(self):
        # Initialize instance variables.
        self.mqtt_client = None
        self.message_data = None
        self.setup_mqtt()
    
    def setup_mqtt(self):
        # Create and configure the MQTT client if it hasn't been initialized.
        if self.mqtt_client is None:
            self.mqtt_client = mqtt.Client()
            self.mqtt_client.on_connect = self.on_connect
            self.mqtt_client.on_message = self.on_message
            self.mqtt_client.connect("mqtt.eclipseprojects.io", 1883, 60)
            self.mqtt_client.loop_start()
    
    def on_connect(self, client, userdata, flags, rc):
        print("Connected with result code " + str(rc))
        client.subscribe("robot/signal")

    def on_message(self, client, userdata, msg):
        # Update message_data with the received MQTT message.
        self.message_data = msg.payload.decode()
        print("Received message: " + self.message_data)
        # Safely expire the component solution on the main thread.
        try:
            ghenv.Component.ExpireSolution(True)
        except Exception as e:
            self.message_data = "Error expiring solution: " + str(e)
    
    def RunScript(self, x, y):
        # When the component is executed, check if a new MQTT message was received.
        output = "Hello Python 3 in Grasshopper! Subscription active."
        if self.message_data:
            output = self.message_data
        print(output)
        return output

But Rhino immediately crashes. Any suggestions why?

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