code: def _create_step_with_required_fields(self):
      return NotebookJobStep(
          name=STEP_NAME,
          display_name=DISPLAY_NAME,
          description=DESCRIPTION,
          notebook_job_name=NOTEBOOK_JOB_NAME,
          input_notebook=INPUT_NOTEBOOK,
          image_uri=IMAGE_URI,
          kernel_name=KERNEL_NAME,
      )
  
imports: from __future__ import absolute_import
  import unittest
  from mock import Mock, patch
  from sagemaker.workflow.notebook_job_step import NotebookJobStep
  from sagemaker.workflow.functions import Join
label_desc: Use image node_id 15 for calling the TestNotebookJobStep obj's underlying member method code with example usage: obj._create_step_with_required_fields() and returns: NotebookJobStep