code: def check_local_file(file_path, message):
      while not os.path.isfile(file_path):
          print(f"File {file_path} doesn't exist.")
          file_path = input(message)
      return file_path
  
imports: import datetime
  import os
  import subprocess
  from absl import app
  from absl import flags
  from google.cloud import storage
label_desc: Use image node_id 4 for calling a global function with example usage: check_local_file(file_path, message) and returns: file_path