I was generally using the code below to update my project files.
appcfg.py -A project_name -V 1 update c:\myapp\
But now I'm getting an error. That I am not authorized by cred_policy. As a result of my research, I realized that appcfg.py is no longer used. How can I update my project in the easiest way right now?
Use gcloud app deploy command instead of appcfg.py.
It would look something like this: gcloud app deploy c:\myapp\app.yaml --project= project_name
Follow the below link for more information.
https://cloud.google.com/appengine/docs/standard/java/tools/migrating-from-appcfg-to-gcloud