[PyMOL] How do I get current selection name from python?

[Boris K. <khe...@gm...>]

I want to save current selection as a uniquetly-named pdb file. So I need
tempfile of python.

So I write def, and I want it have current selection as default one (not
the '(all)'). How do I do that?

I think it will be somewhere under
 cmd.get_session()

I read the sources, but couldn't find a single instance where current
selection would be a default one.