`master_auth` in list_cluster response, is missing username and password

Question

I have enabled Basic Authentication in a given cluster, but in list_cluster, both of the username and password fields are missing. Although I can see If I use the gcloud cli.

Please let me know how can I view the Basic Authentication credentials using google-cloud-container library.

from google.oauth2 import service_account
from google.cloud import container_v1

credentials = service_account.Credentials.from_service_account_file(
            "/tmp/.key",
            scopes=["https://www.googleapis.com/auth/cloud-platform"],
    )
    
computeAPI = container_v1.ClusterManagerClient(credentials=credentials)
clusters_list = get_clusters_list(containerAPI, event['projectId'])
    for cluster in clusters_list:
       print("master_auth: ", cluster.master_auth)
       print("password: ", cluster.master_auth.password)
       print("username: ", cluster.master_auth.username)

def get_clusters_list(containerAPI, project):
    clusters_list = []
    request = containerAPI.list_clusters(parent="projects/{}/locations/-".format(project))
    if request != None and hasattr(request, 'clusters'):
        clusters_list.extend(request.clusters)
    return clusters_list

OUTPUT

master_auth: cluster_ca_certificate: "LS0tLS1CRUdJTiBDRVJUSUZJQ0FURS0tLS0tCk1JSURDekNDQWZPZ0F3SUJBZ0lRTW94N01sc3hRalVEMXZwOHp6K09TekFOQmdrcWhraUc5dzBCQVFzRkFEQXYKTVMwd0t3WURWUVFERXlRd01qWmpaalk0WXkwd01URm1MVFE0TW1FdFlqWTVaaTFrTldVMU9UYzBORGd6TVRBdwpIaGNOTWpBd05USXhNVGN4TURBMFdoY05NalV3TlRJd01UZ3hNREEwV2pBdk1TMHdLd1lEVlFRREV5UXdNalpqClpqWTRZeTB3TVRGbUxUUTRNbUV0WWpZNVppMWtOV1UxT1RjME5EZ3pNVEF3Z2dFaU1BMEdDU3FHU0...."

password:
username:

P.S I am running this code on AWS Lambda.

python version: 3.7

google-cloud-container version: 0.5.0

OS: Amazon Linux

AWS AMI: amzn2-ami-hvm-2.0.20200406.0-x86_64-gp2