code: def allowed_file(filename):
      return (
          "." in filename
          and filename.rsplit(".", 1)[1].lower() in ALLOWED_EXTENSIONS
      )
  
file_path: evadb/apps/rest/run_evadb.py
imports: import os
  from pathlib import Path
  from flask import Flask, flash, redirect, request
  from flask_restful import Api
  from werkzeug.utils import secure_filename
  import evadb
label_desc: Use image node_id 2 for calling a global function with example usage: allowed_file(filename) and returns: unknown