Is there a unique ID corresponding to each Group / User in the GroupWise address book?


We have two address books - AddressBook1, AddressBook2.
1) Create a Group "Group1" corresponding to each of these AddressBooks
2) Add some members to each of these Group1's.
3) Add a Group "Group2" to AddressBook2
4) Add AddressBook1.Group1 and AddressBook2.Group1 to be members of Group2

How do we differentiate which Group1 we are referring to, When we are iterating though the members of Group2 via object API (assume both the Group1's have the same members as well).