Extended ACLs: Who Was Granted Access?

A shared file /data/shared has extended POSIX ACLs beyond its normal owner/group/other bits (the names differ per session). Audit them: exactly one named USER has been granted read-write access via an ACL entry. Another user only got read, and a GROUP was also granted read-write, but a group isn't a user. Identify that user and record their name to /root/answers/acl_user.txt.

getfacl /data/shared

Look for a 'user:NAME:rw-' line (a named user entry). Record NAME.