How to fetch value in new Student document from Student Applicant?

I added custom field “IIN” to document Student Applicant and also I added custom field “IIN” to document Student.
I need when to create new Student Applicant and fill in “IIN” after submiting document to add value of IIN to document Student.

How to do this?
I think I need use Fetch From? What command should I use?

For documents Student from Studen Applicant I used command:


But now I need use similiar fetch on from Student Leave Application to Student Attendance for select type of value.
And the same way doesn’t work for me.
How to do it?

I’m surprised that doc.item_code.IIN is working for you. It should be just doc.IIN.

doen’t work doc.absent anyway.