 It seems that --elasticsearch-version is not use.
return {
        'DomainStatus': {
            'ARN': 'arn:aws:es:%s:%s:domain/%s' % (aws_stack.get_region(), TEST_AWS_ACCOUNT_ID, domain_name),
            'Created': True,
            'Deleted': deleted,
            'DomainId': '%s/%s' % (TEST_AWS_ACCOUNT_ID, domain_name),
            'DomainName': domain_name,
            'ElasticsearchClusterConfig': {
                'DedicatedMasterCount': 1,
                'DedicatedMasterEnabled': True,
                'DedicatedMasterType': 'm3.medium.elasticsearch',
                'InstanceCount': 1,
                'InstanceType': 'm3.medium.elasticsearch',
                'ZoneAwarenessEnabled': False
            },
            'ElasticsearchVersion': '7.1',
            'Endpoint': aws_stack.get_elasticsearch_endpoint(domain_name),
            'Processing': False,
            'EBSOptions': {
                'EBSEnabled': True,
                'VolumeType': 'gp2',
                'VolumeSize': 10,
                'Iops': 0
            },
            'CognitoOptions': {
                'Enabled': False
            },
        }
    }
def start_elasticsearch_instance():