code: def exists(self, object_name):
      try:
          self.client.head_object(Bucket=self.bucket, Key=object_name)
          return True
      except botocore.exceptions.ClientError:
          return False
  
imports: import os
  from typing import Dict, Optional, Union
  import boto3
  import botocore
  import pydantic
  from structlog import get_logger
  from tenacity import retry
  from modelkit.assets import errors
  from modelkit.assets.drivers.abc import StorageDriver, StorageDriverSettings
  from modelkit.assets.drivers.retry import retry_policy
label_desc: Use image node_id 7 for calling the S3StorageDriver obj's underlying member method code with example usage: obj.exists(object_name) and returns: True, False