code: def _cleanup(session=None):
      if session is None:
          session = Session()
      session.query(Pool).filter(
          Pool.pool != Pool.DEFAULT_POOL_NAME
      ).delete()
      session.commit()
      add_default_pool_if_not_exists()
      session.close()
  
imports: from __future__ import annotations
  import json
  from contextlib import redirect_stdout
  from io import StringIO
  import pytest
  from airflow import models, settings
  from airflow.cli import cli_parser
  from airflow.cli.commands import pool_command
  from airflow.models import Pool
  from airflow.settings import Session
  from airflow.utils.db import add_default_pool_if_not_exists
label_desc: Use image node_id 3 for calling the TestCliPools obj's underlying member method code with example usage: obj._cleanup(session) without return types