import json with open("/etc/ssowat/conf.json.persistent", "r", encoding='utf-8') as jsonFile: data = json.load(jsonFile) if "skipped_urls" in data: data["skipped_urls"].append("/_matrix") else: data["skipped_urls"] = ["/_matrix"] with open("/etc/ssowat/conf.json.persistent", "w", encoding='utf-8') as jsonFile: jsonFile.write(json.dumps(data, indent=4, sort_keys=True))