LDAP Attribute objectGUID

**Describe your question/**

I want to migrate to Authentik for authentication for all of my apps. My users are in AD. I'm starting with NextCloud. I'm currently using NextCloud with LDAP integration. Using this method, NextCloud uses the LDAP attribute objectGUID as the user ID in NextCloud. My goal is to migrate the existing users from LDAP authentication to Authentik while preserving the NextCloud user IDs, which are actually retrieved from AD via the objectGUID attribute.

My first step in trying to do this was to retrieve the objectGUID attribute via a custom Property Mapping, however I'm way in over my head trying to create the python expression.

My questions are

A.) Is this worth pursuing, or is the premise of what I'm trying to do flawed in some way
B.) If this is the right way to do this, how would I go about retrieving this LDAP attribute and append it to my Authentik users?

**Relevant info**
Latest version, brand new docker install

**Screenshots**
If applicable, add screenshots to help explain your problem.

**Logs**
Output of docker-compose logs or kubectl logs respectively

**Version and Deployment (please complete the following information):**

- authentik version: [2024.8.3]
- Deployment: docker-compose

**Additional context**
Add any other context about the problem here.

No source files, tests, or entry points are named. Start by reviewing the custom Property Mapping and LDAP integration areas referenced in the issue, along with the Python expression requirements. Done would require a confirmed approach for retrieving objectGUID and preserving existing NextCloud user IDs, but the issue does not define an implementation or verification path.

Written by the indexing model from the issue text.