text: """DNS Authenticator for CloudXNS DNS."""
  import logging
  
  import zope.interface
  from lexicon.providers import cloudxns
  
  from certbot import errors
  from certbot import interfaces
  from certbot.plugins import dns_common
  from certbot.plugins import dns_common_lexicon
  
  logger = logging.getLogger(__name__)
  
  ACCOUNT_URL = 'https://www.cloudxns.net/en/AccountManage/apimanage.html'
  
  
  @zope.interface.implementer(interfaces.IAuthenticator)
  @zope.interface.provider(interfaces.IPluginFactory)
  class Authenticator(dns_common.DNSAuthenticator):
      """DNS Authenticator for CloudXNS DNS
  
      This Authenticator uses the CloudXNS DNS API to fulfill a dns-01 challenge.
      """
  
      description = 'Obtain certs using a DNS TXT record (if you are using CloudXNS for DNS).'
      ttl = 60
  
      def __init__(self, *args, **kwargs):
          super(Authenticator, self).__init__(*args, **kwargs)
          self.credentials = None
  
      @classmethod
      def add_parser_arguments(cls, add):  # pylint: disable=arguments-differ
          super(Authenticator, cls).add_parser_arguments(add, default_propagation_seconds=30)
          add('credentials', help='CloudXNS credentials INI file.')
  
      def more_info(self):  # pylint: disable=missing-docstring,no-self-use
          return 'This plugin configures a DNS TXT record to respond to a dns-01 challenge using ' + \
                 'the CloudXNS API.'
  
      def _setup_credentials(self):
          self.credentials = self._configure_credentials(
              'credentials',
              'CloudXNS credentials INI file',
              {
                  'api-key': 'API key for CloudXNS account, obtained from {0}'.format(ACCOUNT_URL),
                  'secret-key': 'Secret key for CloudXNS account, obtained from {0}'
                                .format(ACCOUNT_URL)
              }
          )
  
      def _perform(self, domain, validation_name, validation):
          self._get_cloudxns_client().add_txt_record(domain, validation_name, validation)
  
      def _cleanup(self, domain, validation_name, validation):
          self._get_cloudxns_client().del_txt_record(domain, validation_name, validation)
  
      def _get_cloudxns_client(self):
          return _CloudXNSLexiconClient(self.credentials.conf('api-key'),
                                        self.credentials.conf('secret-key'),
                                        self.ttl)
  
  
  class _CloudXNSLexiconClient(dns_common_lexicon.LexiconClient):
      """
      Encapsulates all communication with the CloudXNS via Lexicon.
      """
  
      def __init__(self, api_key, secret_key, ttl):
          super(_CloudXNSLexiconClient, self).__init__()
  
          self.provider = cloudxns.Provider({
              'auth_username': api_key,
              'auth_token': secret_key,
              'ttl': ttl,
          })
  
      def _handle_http_error(self, e, domain_name):
          hint = None
          if str(e).startswith('400 Client Error:'):
              hint = 'Are your API key and Secret key values correct?'
  
          return errors.PluginError('Error determining zone identifier for {0}: {1}.{2}'
                                    .format(domain_name, e, ' ({0})'.format(hint) if hint else ''))
  