code: def is_file(path: str) -> str:
      """
      Returns true or false if path points to an existing file
      :param path: A path to a file
      :return: True if file exists and is a file, False otherwise
      :raises FileNotFoundError if file does not exist
      """
      if not os.path.exists(path):
          raise FileNotFoundError(
              """File '{}' not found""".format(path)
          )
      return os.path.isfile(path)
  
imports: import argparse
  import ctypes
  import glob
  import logging
  import os
  import re
  import sys
  from itertools import chain
  from subprocess import CalledProcessError, check_output
  from typing import Dict, List, Optional
  import boto3
  import botocore.exceptions
  import yaml
label_desc: Use image node_id 20 for calling a global function with example usage: is_file(path) and returns: os