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VirtualBox shell - extensible python interface. Have not yet tried it, but probably should. It's only barely mentioned in the SDK document, but it looks like the some source is installed as a Python site package. The main program is (relative to installation directory)
sdk/bindings/glue/python/sample/vboxshell.py
On my machine that's /usr/lib/virtualbox/sdk/bindings/glue/python/sample/vboxshell.py
Web service - exports nearly complete API. Can be used via Java, Python, or as raw web service. I don't think it's appropriate for us. We don't need the ability to control VMs remotely; I expect VM commands will be issued from the host.
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