Access only to delete attachments added by my group members

[Ana39]

Hi there, I am developing a new project in a custom table. I have two groups working in one custom task.
I need to prevent one group of people from deleting the files added by the other group of people. 

For example, I have group A and B working on the task. The task has one attached file "fileone" added by the group of people "a" with "a-role". The "fileone" cannot be deleted by members of group "b".

While all this happens, I need the mmbers of team "B" to be able to manage their own attachments as wanted. 
In the same way, the "A" people cannot delete the files added by the team "B"

Can you please help me with that? 
Thanks in advance! 

-Ana

[Sohail Khilji · Accepted solution]

Create a delete ACL with role and below advance script.

answer = gs.getUser().getName() == current.sys_created_by;

[Ana39]

Thanks for that, but the table of attachments is global so if I do that... I am afraid that it might impact all the other attachments 😬