code: def _check_for_existing_cluster(
      cluster_name: str, project_id: str, creds: Credentials
  ):
      """checks for an existing cluster and confirms new cluster creation with user
  
      Args:
      cluster_name: name of cluster to create
      project_id: project id
      creds: credentials
  
      Returns:
      True if cluster creation should proceed, False otherwise
      """
  
      clusters = Cluster.list(project_id=project_id, creds=creds)
  
      if clusters is None:
          return False
  
      if len(clusters) == 0:
          return True
  
      if cluster_name in clusters:
          logging.error(
              "cluster {} already exists".format(cluster_name)
          )
          return False
  
      logging.info(
          "{} clusters already exist for this project:".format(
              len(clusters)
          )
      )
      for c in clusters:
          logging.info(c)
  
      return util.user_verify(
          "Do you really want to create a new cluster?", default=False
      )
  
imports: import json
  import logging
  import os
  import pprint
  from datetime import datetime
  from typing import Any, Dict, List, Optional
  import googleapiclient
  from google.auth.credentials import Credentials
  from kubernetes.client import V1Job
  import caliban.cli
  import caliban.config
  import caliban.platform.cloud.util
  import caliban.platform.gke.constants
  import caliban.platform.gke.util
  import caliban.util
  import caliban.util.metrics
  from caliban.history.util import create_experiments, generate_container_spec, get_mem_engine, get_sql_engine, session_scope
  from caliban.platform.cloud.core import generate_image_tag
  from caliban.platform.gke.cluster import Cluster
label_desc: Use image node_id 3 for calling a global function with example usage: _check_for_existing_cluster(cluster_name, project_id, creds) and returns: util, False, True, False