OSP 16.1 Overcloud Deployment failing py error TypeError: inet_pton()

Issue

• overcloud deploy is failing with the below exception:

Exception occured while running the command
Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/tripleoclient/command.py", line 32, in run
    super(Command, self).run(parsed_args)
  File "/usr/lib/python3.6/site-packages/osc_lib/command/command.py", line 41, in run
    return super(Command, self).run(parsed_args)
  File "/usr/lib/python3.6/site-packages/cliff/command.py", line 185, in run
    return_code = self.take_action(parsed_args) or 0
  File "/usr/lib/python3.6/site-packages/tripleoclient/v1/overcloud_deploy.py", line 1125, in take_action
    self._deploy_postconfig(stack, parsed_args)
  File "/usr/lib/python3.6/site-packages/tripleoclient/v1/overcloud_deploy.py", line 573, in _deploy_postconfig
    [x for x in no_proxy_list if x is not None])
  File "/usr/lib/python3.6/site-packages/tripleoclient/v1/overcloud_deploy.py", line 573, in <listcomp>
    [x for x in no_proxy_list if x is not None])
  File "/usr/lib/python3.6/site-packages/tripleoclient/utils.py", line 428, in bracket_ipv6
    socket.inet_pton(socket.AF_INET6, address)
TypeError: inet_pton() argument 2 must be str, not None
inet_pton() argument 2 must be str, not None