[Python] Paho MQTT "Unsupported callback API version" error

I am trying to implement Paho Python MQTT and connect to an online broker but the code seems to through an error.

ValueError: Unsupported callback API version: version 2.0 added a callback_api_version, see migrations.md for details
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I was trying to implement a simple paho client example from the given website; the following will reproduce the issue:

from paho.mqtt import client as mqtt_client
import random

broker = 'broker.emqx.io'
port = 1883
topic = "python/mqtt"
client_id = f'python-mqtt-{random.randint(0, 1000)}'
client = mqtt_client.Client(client_id)

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