Set focusable property via script?

[Marian Petrides]

I have a stack with a very large number of cards.  Now that I am done 
entering text into the fields on these cards, I want to be sure that 
each field is locked and that it is not focusable.

Is there a way to set these properties from script?  I'd hate to have 
to check each and every one manually.

And, yes, I did look in the dox, even searched but I don't see a 
property called focusable, nor one called locked.

Thanks.

M