How to concatenate manager person numbers from hierarchy in HCM Extract?

Summary:

Content (please ensure you mask any confidential information):

urrently my extract structure is like this:

PER_EXT_PERSON_MANAGERS_HIERARCHY_UE

In this UE, I was not getting the manager person number details for every level.
So I used PER_EXT_SEC_PERSON_UE and joined it with the hierarchy UE to get the manager person numbers.

Now I am able to retrieve the manager person numbers like below in the extract output:

7007 

990046

016957

015582

(as shown in the attached image)

However, my goal is to concatenate all manager person numbers into a single value like:

(70079,90046,016957,015582)

What is the recommended way to concatenate these values in