code: def test_default_already_cached(sagemaker_session):
      existing_default = "mydefaultbucket"
      sagemaker_session._default_bucket = existing_default
  
      bucket_name = sagemaker_session.default_bucket()
  
      create_calls = (
          sagemaker_session.boto_session.resource().create_bucket.mock_calls
      )
      assert bucket_name == existing_default
      assert create_calls == []
  
file_path: sagemaker-python-sdk/tests/unit/test_default_bucket.py
imports: from __future__ import absolute_import
  import datetime
  import pytest
  from botocore.exceptions import ClientError
  from mock import MagicMock
  import sagemaker
label_desc: Use image node_id 7 for calling a global function with example usage: test_default_already_cached(sagemaker_session) without return types