code: def url_exists(url: str) -> bool:
      try:
          return (
              requests.head(url, allow_redirects=True).status_code
              == 200
          )
      except requests.exceptions.RequestException:
          logger.exception(f"Failed to check url exists: {url}")
          return False
  
imports: import collections
  import hashlib
  import json
  import os
  import random
  import string
  import subprocess
  import time
  from typing import TYPE_CHECKING, Any, Dict, List, Optional, Tuple
  import requests
  from ray_release.logger import logger
label_desc: Use image node_id 3 for calling a global function with example usage: url_exists(url) and returns: unknown, False