code: @Override
      public DBSnapshot modifyDBSnapshot(ModifyDBSnapshotRequest request) {
          request = beforeClientExecution(request);
          return executeModifyDBSnapshot(request);
      }
docs: <p>
  Updates a manual DB snapshot, which can be encrypted or not encrypted, with a new engine version.
  </p>
  <p>
  Amazon RDS supports upgrading DB snapshots for MySQL and Oracle.
  </p>
  
  @param modifyDBSnapshotRequest
  @return Result of the ModifyDBSnapshot operation returned by the service.
  @throws DBSnapshotNotFoundException
  <i>DBSnapshotIdentifier</i> doesn't refer to an existing DB snapshot.
  @sample AmazonRDS.ModifyDBSnapshot
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/rds-2014-10-31/ModifyDBSnapshot" target="_top">AWS API
  Documentation</a>