How to Create SDM mapping on parent member and use @listname function?

Summary:

Summary: The business context is that our customer wants to breakdown the balance sheet accounts 'loans and borrowings - current' and 'loans and borrowings - non-current', and ideally we can map these accounts to SDM and analyse further within SDM to support the loans and borrowings disclosure note. However the challenge is that as our Balance Sheet hierarchy goes down to GL code level detail (i.e. at base level), this is is already much too detailed to breakdown in SDM, we would rather break down at parent / disclosed level and not on GL code level."

So, I have created template in which I want to create mapping for the Entity and Account (but not only on 1 leaf member as specified to select I want to use the function mentioned which is "@Listname" and to include a parent member).