code: def export_domain(self, domain):
          
          uri = "/domains/%s/export" % utils.get_id(domain)
          resp, resp_body = self._async_call(uri, method="GET",
                  error_class=exc.NotFound)
          return resp_body.get("contents", "")
docs: Provides the BIND (Berkeley Internet Name Domain) 9 formatted contents
          of the requested domain. This call is for a single domain only, and as
          such, does not provide subdomain information.
  
          Sample export:
              {u'accountId': 000000,
               u'contentType': u'BIND_9',
               u'contents': u'example.com.\t3600\tIN\tSOA\tns.rackspace.com. '
                  'foo@example.com. 1354202974 21600 3600 1814400 500'
                  'example.com.\t3600\tIN\tNS\tdns1.stabletransit.com.'
                  'example.com.\t3600\tIN\tNS\tdns2.stabletransit.com.',
               u'id': 1111111}