How to use the dns-packet.RECURSION_AVAILABLE function in dns-packet

const question = (requestPacket.questions && requestPacket.questions.length === 1) ? requestPacket.questions[0] : null
  if (question === null || 
    (question.type !== 'A' && question.type !== 'AAAA') ||
    !question.name.endsWith('.' + conf.newTld)) return deferToDnsFallback(request, requestBody)
  log('Responding to query for new TLD')

  // If we ask for our TLD on localhost, we'll just send back the fixed local
  // IPs. However, if our host is something else, we defer to the fallback and
  // just change the answer names so we get SOAs, NSs, As, CNAMEs, etc.
  let responsePacket: dnsPacket.Packet
  if (conf.proxyDnsTo === 'localhost') {
    log('Sending back localhost IPs')
    responsePacket = {
      id: requestPacket.id,
      type: 'response',
      flags: dnsPacket.RECURSION_DESIRED | dnsPacket.RECURSION_AVAILABLE,
      questions: requestPacket.questions,
      answers: [{
        type: question.type,
        class: 'IN',
        name: question.name,
        data: question.type === 'A' ? '127.0.0.1' : '::1',
        ttl: 600
      }]
    }
  } else {
    // Update the request packet to do a different host
    log('Proxying requested DNS name to: ', conf.proxyDnsTo)
    const origName = question.name
    requestPacket.questions.forEach(q => q.name = conf.proxyDnsTo)
    // Send it off
    const proxiedResponse = await deferToDnsFallback(request, dnsPacket.encode(requestPacket).buffer)

}

  function onlistening () {
    self._interval = setInterval(ontimeoutCheck, self.timeoutChecks)
    self.emit('listening')
  }

  function onclose () {
    self.emit('close')
  }
}

util.inherits(DNS, events.EventEmitter)

DNS.RECURSION_DESIRED = DNS.prototype.RECURSION_DESIRED = packet.RECURSION_DESIRED
DNS.RECURSION_AVAILABLE = DNS.prototype.RECURSION_AVAILABLE = packet.RECURSION_AVAILABLE
DNS.TRUNCATED_RESPONSE = DNS.prototype.TRUNCATED_RESPONSE = packet.TRUNCATED_RESPONSE
DNS.AUTHORITATIVE_ANSWER = DNS.prototype.AUTHORITATIVE_ANSWER = packet.AUTHORITATIVE_ANSWER
DNS.AUTHENTIC_DATA = DNS.prototype.AUTHENTIC_DATA = packet.AUTHENTIC_DATA
DNS.CHECKING_DISABLED = DNS.prototype.CHECKING_DISABLED = packet.CHECKING_DISABLED

DNS.prototype.address = function () {
  return this.socket.address()
}

DNS.prototype.bind = function (...args) {
  const onlistening = args.length > 0 && args[args.length - 1]
  if (typeof onlistening === 'function') {
    this.once('listening', onlistening)
    this.socket.bind(...args.slice(0, -1))
  } else {
    this.socket.bind(...args)

}

  function onlistening () {
    self._interval = setInterval(ontimeoutCheck, self.timeoutChecks)
    self.emit('listening')
  }

  function onclose () {
    self.emit('close')
  }
}

util.inherits(DNS, events.EventEmitter)

DNS.RECURSION_DESIRED = DNS.prototype.RECURSION_DESIRED = packet.RECURSION_DESIRED
DNS.RECURSION_AVAILABLE = DNS.prototype.RECURSION_AVAILABLE = packet.RECURSION_AVAILABLE
DNS.TRUNCATED_RESPONSE = DNS.prototype.TRUNCATED_RESPONSE = packet.TRUNCATED_RESPONSE
DNS.AUTHORITATIVE_ANSWER = DNS.prototype.AUTHORITATIVE_ANSWER = packet.AUTHORITATIVE_ANSWER
DNS.AUTHENTIC_DATA = DNS.prototype.AUTHENTIC_DATA = packet.AUTHENTIC_DATA
DNS.CHECKING_DISABLED = DNS.prototype.CHECKING_DISABLED = packet.CHECKING_DISABLED

DNS.prototype.address = function () {
  return this.socket.address()
}

DNS.prototype.bind = function (...args) {
  const onlistening = args.length > 0 && args[args.length - 1]
  if (typeof onlistening === 'function') {
    this.once('listening', onlistening)
    this.socket.bind(...args.slice(0, -1))
  } else {
    this.socket.bind(...args)