e the identity alias when using the ec2 auth method. Valid choices
            are role_id, instance_id, and image_id. When role_id is selected, the randomly generated ID of the role is
            used. When instance_id is selected, the instance identifier is used as the identity alias name. When
            image_id is selected, AMI ID of the instance is used as the identity alias name
        :type ec2_alias: str | unicode
        :param mount_point: The path the AWS auth method was mounted on.
        :type mount_point: str | unicode
        :return: The response of the request
        :rtype: request.Response
        NzTinvalid iam alias type provided: "{arg}"; supported iam alias types: "{alias_types}"ú