Support encryption for Python outputs

### Feature description

I am doing some task to process sensitive data / secrets using Python script / command. There is encryption for `inputs` and `outputs` by configure `encryption.secret-key` but I am not sure how to configure encryption for the Python outputs.

Start by tracing how encryption.secret-key is applied to existing inputs and outputs in the Python script or command path; the issue names no file or test. Done means Python outputs can be encrypted with that configuration and the behavior is covered by the relevant plugin tests.

Written by the indexing model from the issue text.