def get_next_id(self):
        try:
            query = {'_id': 'last_id'}
            update = {'$inc': {'id': 1}}
            fn = self.db.internal.find_and_modify
            row = fn(query, update, upsert=True, new=True)
        except Exception as e:
            raise DatabaseException(e)
        return row['id']
def ProcessCommandLineArgs(parser, args):
  # TODO(ariblue): Delete this flag entirely at some future data, when the
  # existence of such a flag has been long forgotten.
  if args.output_file:
    parser.error('This flag is deprecated. Please use --output-dir instead.')

  try:
    os.makedirs(args.output_dir)
  except OSError:
    # Do nothing if the output directory already exists. Existing files will
    # get overwritten.
    pass

  args.output_dir = os.path.expanduser(args.output_dir)