code: def validate_pipeline(url, pipeline_id, auth, verify_ssl):
      
  
      validate_result = requests.get(url + '/' + pipeline_id + '/validate', headers=X_REQ_BY, auth=auth, verify=verify_ssl)
      validate_result.raise_for_status()
      previewer_id = validate_result.json()['previewerId']
      poll_validation_status(url, pipeline_id, previewer_id, auth, verify_ssl)
  
      preview_result = requests.get(url + '/' + pipeline_id + '/preview/' + validate_result.json()['previewerId'], headers=X_REQ_BY, auth=auth, verify=verify_ssl)
      logging.debug('result content: {}'.format(preview_result.content))
  
      return preview_result.json()
docs: Validate a pipeline and show issues.
  
      Args:
          url         (str): the host url in the form 'http://host:port/'.
          pipeline_id (str): the ID of of the exported pipeline.
          auth      (tuple): a tuple of username, and password.
          verify_ssl (bool): whether to verify ssl certificates
  
      Returns:
          dict: the response json