Do the sbc[x]Dependencies install dependencies?

[stuartofmt]

I'm putting together a plugin that uses python. I have three (related) questions.

1. Can I use a python (3.4x) script, as part of a plugin, with a non-sbc printer e.g. Duet2.
2. Do the sbc[x]Dependencies manifest entries just trigger a check or is there an attempt to install the dependencies?
3. Is there any need to use dsf-python?

Thanks in advance