Help needed for initializing SAMR connection against AD

Hello team,

What I am trying to do is to create a simple user in AD and then reset
it's password so that I am able to log in with it and do something as
that user. This is all to be done with Python bindings for a unittest.

What I have done is that I create the user which is a breeze -- no
problem. Here comes the tricky part when I have to reset the password.
Number of ways to do it: Kerberos, SAMR etc. I chose SAMR because there
are already Python wrappings for it. There are number of code examples
in Samba like:

source4/scripting/python/examples/samr.py
source4/scripting/python/samba/tests/dcerpc/sam.py
source4/scripting/python/samba/tests/dcerpc/bare.py

I did looked in them all. Although I couldn't figure out how can I
authenticate against MS Active Directory server using it and then send
request to change password of a given user.

If someone has any clue I would appreciate it.

Regards,

Zahari