Where is nonlocals()?

How do I obtain the non-local variables for the current scope? The functions vars, locals, and globals exist, but is there a function to get the nonlocals?

Why aren't the nonlocals listed when calling vars?

Update

My issue is that there's no way to enumerate the variables available in the current scope, as neither vars or globals includes the non-locals AFAICT.

I frequently use vars in code such as the following:

'{meh[0]}/{meh[3]} {a}{b}{c}'.format(**vars())

Which fails if any of these variables are in the scope of a containing function.