code: def get_available_ip6(self, id_network6):
          
  
          if not is_valid_int_param(id_network6):
              raise InvalidParameterError(
                  u'Network ipv6 identifier is invalid or was not informed.')
  
          url = 'ip/availableip6/' + str(id_network6) + "/"
  
          code, xml = self.submit(None, 'GET', url)
  
          return self.response(code, xml)
docs: Get a available IP in Network ipv6
  
          :param id_network6: Network ipv6 identifier. Integer value and greater than zero.
  
          :return: Dictionary with the following structure:
  
          ::
  
              {'ip6': {'ip6': < available_ip6 >}}
  
          :raise IpNotAvailableError: Network dont have available IP.
          :raise NetworkIPv4NotFoundError: Network was not found.
          :raise UserNotAuthorizedError: User dont have permission to get a available IP.
          :raise InvalidParameterError: Network ipv6 identifier is none or invalid.
          :raise XMLError: Networkapi failed to generate the XML response.
          :raise DataBaseError: Networkapi failed to access the database.