code: def _bucket_exists(bucket_name):
      from botocore.exceptions import ClientError
  
      s3 = boto3.resource("s3")
      try:
          s3.meta.client.head_bucket(Bucket=bucket_name)
      except ClientError as e:
          if e.response["Error"]["Code"] == "404":
              return False
      return True
  
imports: import datetime
  import pytest
  import json
  import os
  from sacred.observers import S3Observer
label_desc: Use image node_id 4 for calling a global function with example usage: _bucket_exists(bucket_name) and returns: True, False