[Samba] Error change DNS backend

[Miguel Angel Coa M.]

Hi,
I update the Samba from 4.10.x to 4.11.9, and update the python (2.7.6 to
3.6.9) . The update process works fine but now try change DNS backend
(intenal to DLZ) and have the next error:

[..................]
[root at sambadc03 ~]# /usr/local/samba/sbin/samba_upgradedns
--dns-backend=BIND9_DLZ
Traceback (most recent call last):
  File "/usr/local/samba/sbin/samba_upgradedns", line 72, in <module>
    import dns.zone, dns.rdatatype
ModuleNotFoundError: No module named 'dns'
[..................]

Python version
[..................]
[root at sambadc03 ~]# python -V
Python 3.6.9
[..................]

Samba version
[..................]
[root at sambadc03 ~]# /usr/local/samba/sbin/samba -V
Version 4.11.9
[..................]

S.O version
[..................]
[root at sambadc03 ~]# cat /etc/redhat-release
CentOS Linux release 7.8.2003 (Core)
[root at sambadc03 ~]#
[..................]

Saludos.
---
Miguel Coa M.