def parse_instance(self, global_params, region, dbi):
        """
        Parse a single RDS instance

        :param global_params:           Parameters shared for all regions
        :param region:                  Name of the AWS region
        :param instance:                Instance
        """
        vpc_id = dbi['DBSubnetGroup']['VpcId'] if 'DBSubnetGroup' in dbi and 'VpcId' in dbi['DBSubnetGroup'] and dbi['DBSubnetGroup']['VpcId'] else ec2_classic
        instance = {}
        instance['name'] = dbi.pop('DBInstanceIdentifier')
        for key in ['InstanceCreateTime', 'Engine', 'DBInstanceStatus', 'AutoMinorVersionUpgrade',
                    'DBInstanceClass', 'MultiAZ', 'Endpoint', 'BackupRetentionPeriod', 'PubliclyAccessible',
                    'StorageEncrypted', 'VpcSecurityGroups', 'DBSecurityGroups', 'DBParameterGroups',
                    'EnhancedMonitoringResourceArn', 'StorageEncrypted']:
                    # parameter_groups , security_groups, vpc_security_groups
            instance[key] = dbi[key] if key in dbi else None
        # If part of a cluster, multi AZ information is only available via cluster information
        if 'DBClusterIdentifier' in dbi:
            api_client = api_clients[region]
            cluster = api_client.describe_db_clusters(DBClusterIdentifier = dbi['DBClusterIdentifier'])['DBClusters'][0]
            instance['MultiAZ'] = cluster['MultiAZ']
        # Save
        manage_dictionary(self.vpcs, vpc_id, VPCConfig(self.vpc_resource_types))
        self.vpcs[vpc_id].instances[instance['name']] = instance
Parse a single RDS instance

        :param global_params:           Parameters shared for all regions
        :param region:                  Name of the AWS region
        :param instance:                Instance