code: def _file_exists(fs, path):
      return fs.exists(path) and fs.is_file(path)
  
file_path: hail/hail/python/hail/utils/tutorial.py
imports: import hail
  from .java import Env, info
  from .misc import new_temp_file, local_path_uri, new_local_temp_dir
  import os
  import zipfile
  from urllib.request import urlretrieve
  from hailtop.utils import sync_retry_transient_errors
label_desc: Use image node_id 3 for calling a global function with example usage: _file_exists(fs, path) and returns: unknown