First set up secrets.py by copying secrets.py.example to secrets.py, and setting the phabricator_certificate field to be the value from 'show secret' at https://phabricator.khanacademy.org/K56
Also fill in slack_webhook_url, taking the value from 'show secret' at https://phabricator.khanacademy.org/K94
You can then deploy by running make deploy.
You can view the logs at https://console.cloud.google.com/logs/viewer?project=khan-webhooks