code: def validate_session():
      """Validate ORM Session."""
      global engine
  
      worker_precheck = conf.getboolean("celery", "worker_precheck")
      if not worker_precheck:
          return True
      else:
          check_session = sessionmaker(bind=engine)
          session = check_session()
          try:
              session.execute(text("select 1"))
              conn_status = True
          except exc.DBAPIError as err:
              log.error(err)
              conn_status = False
          session.close()
          return conn_status
  
imports: from __future__ import annotations
  import atexit
  import functools
  import json
  import logging
  import os
  import sys
  import warnings
  from typing import TYPE_CHECKING, Any, Callable
  import pluggy
  from sqlalchemy import create_engine, exc, text
  from sqlalchemy.orm import scoped_session, sessionmaker
  from sqlalchemy.pool import NullPool
  from airflow import policies
  from airflow.configuration import AIRFLOW_HOME, WEBSERVER_CONFIG, conf
  from airflow.exceptions import RemovedInAirflow3Warning
  from airflow.executors import executor_constants
  from airflow.logging_config import configure_logging
  from airflow.utils.orm_event_handlers import setup_event_handlers
  from airflow.utils.state import State
  from airflow.utils.timezone import local_timezone, parse_timezone, utc
label_desc: Use image node_id 18 for calling a global function with example usage: validate_session() and returns: True, conn_status