code: def check_remote(
      target, device_key, host=None, port=None, priority=100, timeout=10
  ):
      """
      Check the availability of a remote device
  
      Parameters
      ----------
      target: Target
          The wanted compilation target
      device_key: string
          device key of registered device in tracker
      host: host, optional
          The host address of rpc tracker.
          If is none, will use environment variable "TVM_TRACKER_HOST"
      port: int, optional
          The port address of rpc tracker.
          If is none, will use environment variable "TVM_TRACKER_PORT"
      priority: int, optional
          The priority of this request, larger is more prior
      timeout: float, optional
          The timeout of this check (units: seconds).
  
      Returns
      -------
      available: bool
          True if can find available device
      """
  
      def _check():
          logger.debug("waiting for device...")
          remote = request_remote(device_key, host, port, priority)
          dev = remote.device(str(target))
          while not dev.exist:  # wait until we get an available device
              pass
          logger.debug("device available")
  
      t = threading.Thread(target=_check)
      t.start()
      t.join(timeout)
  
      remote = request_remote(device_key, host, port, priority)
      dev = remote.device(str(target))
      return dev.exist
  
imports: import contextlib
  import logging
  import os
  import shutil
  import tempfile
  import threading
  import time
  import traceback
  import typing
  import warnings
  from collections import namedtuple
  from random import getrandbits
  import tvm._ffi
  import tvm.ir.transform
  from tvm import nd
  from tvm import rpc
  from tvm.autotvm.env import AutotvmGlobalScope, reset_global_scope
  from tvm.contrib import ndk, stackvm, tar
  from tvm.contrib.popen_pool import PopenPoolExecutor
  from tvm.driver import build
  from tvm.error import TVMError
  from tvm.target import Target
  from ..env import AutotvmGlobalScope
  from ..task.space import InstantiationError
  from ..utils import get_const_tuple
  from .measure import Builder, MeasureErrorNo, MeasureResult, Runner
label_desc: Use image node_id 5 for calling a global function with example usage: check_remote(target, device_key, host, port, priority, timeout) and returns: dev