code: public TableRow getRow(final String pos) throws FastOdsException, IOException {
          return this.builder.getRow(this, this.appender, pos);
      }
docs: Return a row from a position
  
  @param pos the position, e.g. A5
  @return the row
  @throws FastOdsException if the index is invalid
  @throws IOException      if the row was flushed