Subscription-manager commands fails with error `ValueError: Invalid IPv6 URL`

Issue

• Subscription-manager commands are throwing below error on the system which is configured to use Proxy:-

  # subscription-manager config
  Traceback (most recent call last):
    File "/sbin/subscription-manager", line 9, in <module>
      load_entry_point('subscription-manager==1.24.45', 'console_scripts', 'subscription-manager')()
    File "/usr/lib64/python2.7/site-packages/subscription_manager/scripts/subscription_manager.py", line 86, in main
      return managercli.ManagerCLI().main()
    File "/usr/lib64/python2.7/site-packages/subscription_manager/managercli.py", line 2985, in __init__
      CLI.__init__(self, command_classes=commands)
    File "/usr/lib64/python2.7/site-packages/subscription_manager/cli.py", line 101, in __init__
      cmd = clazz()
    File "/usr/lib64/python2.7/site-packages/subscription_manager/managercli.py", line 1563, in __init__
      attr='addons', commands=['unset', 'add', 'remove'])
    File "/usr/lib64/python2.7/site-packages/subscription_manager/managercli.py", line 565, in __init__
      self.store = self._get_synced_store()
    File "/usr/lib64/python2.7/site-packages/subscription_manager/managercli.py", line 600, in _get_synced_store
      uep = inj.require(inj.CP_PROVIDER).get_consumer_auth_cp()
    File "/usr/lib64/python2.7/site-packages/subscription_manager/cp_provider.py", line 110, in get_consumer_auth_cp
      restlib_class=self.restlib_class)
    File "/usr/lib64/python2.7/site-packages/rhsm/connection.py", line 817, in __init__
      info = utils.get_env_proxy_info()
    File "/usr/lib64/python2.7/site-packages/rhsm/utils.py", line 225, in get_env_proxy_info
      info = parse_url(proxy_info, default_port=DEFAULT_PROXY_PORT)
    File "/usr/lib64/python2.7/site-packages/rhsm/utils.py", line 147, in parse_url
      result = six.moves.urllib.parse.urlparse(good_url)
    File "/usr/lib64/python2.7/urlparse.py", line 142, in urlparse
      tuple = urlsplit(url, scheme, allow_fragments)
    File "/usr/lib64/python2.7/urlparse.py", line 209, in urlsplit
      raise ValueError("Invalid IPv6 URL")
  ValueError: Invalid IPv6 URL
  

  # subscription-manager identity
  Traceback (most recent call last):
    File "/usr/sbin/subscription-manager", line 11, in <module>
      load_entry_point('subscription-manager==1.28.21', 'console_scripts', 'subscription-manager')()
    File "/usr/lib64/python3.6/site-packages/subscription_manager/scripts/subscription_manager.py", line 87, in main
      return managercli.ManagerCLI().main()
    File "/usr/lib64/python3.6/site-packages/subscription_manager/managercli.py", line 3365, in main
      ret = CLI.main(self)
    File "/usr/lib64/python3.6/site-packages/subscription_manager/cli.py", line 183, in main
      return cmd.main()
    File "/usr/lib64/python3.6/site-packages/subscription_manager/managercli.py", line 530, in main
      self.cp = self.cp_provider.get_consumer_auth_cp()
    File "/usr/lib64/python3.6/site-packages/subscription_manager/cp_provider.py", line 156, in get_consumer_auth_cp
      client_version=self.get_client_version()
    File "/usr/lib64/python3.6/site-packages/rhsm/connection.py", line 966, in __init__
      super(UEPConnection, self).__init__(user_agent=user_agent, **kwargs)
    File "/usr/lib64/python3.6/site-packages/rhsm/connection.py", line 181, in __init__
      info = utils.get_env_proxy_info()
    File "/usr/lib64/python3.6/site-packages/rhsm/utils.py", line 248, in get_env_proxy_info
      info = parse_url(proxy_info, default_port=DEFAULT_PROXY_PORT)
    File "/usr/lib64/python3.6/site-packages/rhsm/utils.py", line 170, in parse_url
      result = six.moves.urllib.parse.urlparse(good_url)
    File "/usr/lib64/python3.6/urllib/parse.py", line 369, in urlparse
      splitresult = urlsplit(url, scheme, allow_fragments)
    File "/usr/lib64/python3.6/urllib/parse.py", line 437, in urlsplit
      raise ValueError("Invalid IPv6 URL")
  ValueError: Invalid IPv6 URL