Using version 1.7.0 of the API, this code snippet works fine:
from arcgis.gis import server
user = '<admin user>'
pswd = '<password>'
server_base_url = "https://<server>/<webadaptor>"
gis_server = server.Server(url=f"{server_base_url}/admin",
token_url=f"{server_base_url}/tokens/generateToken",
username=user,
password=pswd)
service = gis_server.content.get('<Service Name>', folder='<Service Folder>')
service.service.status
{'configuredState': 'STARTED', 'realTimeState': 'STARTED'}
However, in 1.8.2 the service status returns:
{'status': 'error', 'messages': ["Unauthorized access. Token not found. You can generate a token using the 'generateToken' operation."], 'code': 499}