You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: DNS_test.rb
    path of file: ./repos/rbs/test/stdlib/resolv
    
    the code of the file until where you have to start completion: require_relative '../test_helper'
require 'resolv'

class ResolvDNSSingletonTest < Test::Unit::TestCase
  include TestHelper
  library 'resolv'
  testing 'singleton(::Resolv::DNS)'

  def test_allocate_request_id
   
    
  def test_open
    assert_send_type  '(Hash[Symbol, untyped]) -> Resolv::DNS',
      Resolv::DNS, :open, :nameserver => ["8.8.8.8"]
    assert_send_type  '(Hash[Symbol, untyped]) { (Resolv::DNS) -> void } -> void',
      Resolv::DNS, :open, :nameserver => ["8.8.8.8"] do |c| c; end
  rescue Errno::ECONNREFUSED
    omit "Connection refused with environmental issue"
  end

  def test_random
    assert_send_type  '(Numeric) -> Numeric',
      Resolv::DNS, :random, 2
  end
end