code: def get_execution_role(sagemaker_session=None):
      
      if not sagemaker_session:
          sagemaker_session = Session()
      arn = sagemaker_session.get_caller_identity_arn()
  
      if ':role/' in arn:
          return arn
      message = 'The current AWS identity is not a role: {}, therefore it cannot be used as a SageMaker execution role'
      raise ValueError(message.format(arn))
docs: Return the role ARN whose credentials are used to call the API.
      Throws an exception if
      Args:
          sagemaker_session(Session): Current sagemaker session
      Returns:
          (str): The role ARN