I am generating 30 asymmetric units of a protein structure. Now, I want to select different combinations of 5 units which are 30 Angstroms away from the reference and save it as a different file. Here is the command I could work out till now :

fetch 3q2v
symexp sym,3q2v,(3q2v),30
select chains, bychain all within 30 of 3q2v

How to loop in and select only 5 chains at a time obtained from the setup obtained by the above code, and save it in separate files?