code: def sagemaker_session_cn():
      boto_mock = Mock(name="boto_session", region_name="cn-north-1")
      session_mock = MagicMock(
          name="sagemaker_session",
          boto_session=boto_mock,
          boto_region_name="cn-north-1",
          config=None,
          local_mode=False,
      )
      session_mock.account_id.return_value = "234567890123"
      return session_mock
  
file_path: sagemaker-python-sdk/tests/unit/sagemaker/workflow/test_lambda_step.py
imports: from __future__ import absolute_import
  import json
  import pytest
  from mock import Mock, MagicMock
  from sagemaker.workflow.parameters import ParameterInteger, ParameterString
  from sagemaker.workflow.pipeline import Pipeline, PipelineGraph
  from sagemaker.workflow.lambda_step import LambdaStep, LambdaOutput, LambdaOutputTypeEnum
  from sagemaker.lambda_helper import Lambda
  from sagemaker.workflow.steps import CacheConfig
  from tests.unit.sagemaker.workflow.helpers import CustomStep, ordered
label_desc: Use image node_id 1 for calling a global function with example usage: sagemaker_session_cn() and returns: session_mock