@property
def xls():
    """A Legacy Excel Spreadsheet representation of the :class:`Dataset` object, with :ref:`separators`. Cannot be set.

        .. note::

            XLS files are limited to a maximum of 65,000 rows. Use :class:`Dataset.xlsx` to avoid this limitation.

         .. admonition:: Binary Warning

             :class:`Dataset.xls` contains binary data, so make sure to write in binary mode::

                with open('output.xls', 'wb') as f:
                    f.write(data.xls)'
        """
    pass
