update_entity_attribute.py

# coding: utf-8

from pycti import OpenCTIApiClient

# Variables
api_url = "https://demo.opencti.io"
api_token = "YOUR_TOKEN"

# OpenCTI initialization
opencti_api_client = OpenCTIApiClient(api_url, api_token)

# Get the intrusion set APT28
intrusion_set = opencti_api_client.intrusion_set.read(
    filters=[{"key": "name", "values": ["APT28"]}]
)

# Update the description
opencti_api_client.stix_domain_object.update_field(
    id=intrusion_set["id"], input={"key": "description", "value": "This is APT28!"}
)