code: def is_valid_url(url):
      regex = re.compile(
          r"^(?:http|ftp)s?://"  # http:// or https://
          r"(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+(?:[A-Z]{2,6}\.?|[A-Z0-9-]{2,}\.?)|"  # domain...
          r"localhost|"  # localhost...
          r"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})"  # ...or ip
          r"(?::\d+)?"  # optional port
          r"(?:/?|[/?]\S+)$",
          re.IGNORECASE,
      )
      return re.match(regex, url) is not None
  
imports: import os
  import re
  import hashlib
  import requests
  from tqdm import tqdm
label_desc: Use image node_id 3 for calling a global function with example usage: is_valid_url(url) and returns: unknown