Question - LDAP and Samdb.py

[luke morrison]

Just wanted to know 2 things : 

Do attributes come from Samba or the network using LDAP?? So I am looking for various attributes of the Samba server, like Lockout Thresholds for example. Now the samdb.py file does not have this explicitly but does that mean that this attribute does not yet exist? Are the attributes network related, and can be called using LDAP? Or Samba configured in a way where attributes such as these are manually made at some point?

My other question is super simple. How do I find OU of DC using python code. This is giving me more hassle than it deserves? 

Regards

-Luke