Keep Secret Keys Out
You may need to use os.environ.get("SOME_SECRET_KEY")
One of the causes of the local_settings.py anti-pattern is that putting SECRET_KEY, AWS
keys, etc.. values into settings files has problem:

Secrets often should be just that: secret! Keeping them in version control means
that everyone with repository access has access to them.

My question is how to keep all keys as secret?