Make the RAN_UE_NGAP_ID random

[GiovanniColonni]

I'm creating a script that is able to run the UEs inside a bunch of containers and then connect them to open5gs, after this my goal is to capture the traffic and with, a script that is able to follow the exchange of NGAP messages between each UEs, create a .csv file like this:

RAN_UE_NGAP_ID | time | number of msg exchanged
1                                  1,2s  7
..

I'm perfectly able to do that if I run UERASIM in the local machine, but in case of containers these IDs are the same along the containers and so resulting in collisions.
My idea is to let the RAN_UE_NGAP_ID random, in this way I will basically avoid the collisions
Is it possible? if yes, who set this id? the UE or the GNB? because i'm struggling to understand where to start
I'm looking for any suggestions, thank you :)