class_docstr: Default `Resolver` implementation, using `socket.getaddrinfo`.
  
  The `.IOLoop` will be blocked during the resolution, although the
  callback will not be run until the next `.IOLoop` iteration.
  
  .. deprecated:: 5.0
     The default `Resolver` now uses `.IOLoop.run_in_executor`; use that instead
     of this class.
class_docstr_tok: ["Default","`","Resolver","`","implementation",",","using","`","socket.getaddrinfo","`",".","The","`",".IOLoop","`","will","be","blocked","during","the","resolution",",","although","the","callback","will","not","be","run","until","the","next","`",".IOLoop","`","iteration",".","..","deprecated",":",":","5.0","The","default","`","Resolver","`","now","uses","`",".IOLoop.run_in_executor","`",";","use","that","instead","of","this","class","."]
code: def initialize(self) -> None:  # type: ignore
      super().initialize()
  
imports: import asyncio
  import concurrent.futures
  import errno
  import os
  import sys
  import socket
  import ssl
  import stat
  from tornado.concurrent import dummy_executor, run_on_executor
  from tornado.ioloop import IOLoop
  from tornado.util import Configurable, errno_from_exception
  from typing import List, Callable, Any, Type, Dict, Union, Tuple, Awaitable, Optional
label_desc: Use image node_id 1 for calling the BlockingResolver obj's underlying member method code with example usage: obj.initialize() without return types