Returns a list with ids of rows of same column.

        :param hed: The list that represents the table header.
        :type hed: list(list(hatemile.util.html.htmldomelement.HTMLDOMElement))
        :param index: The index of columns.
        :type index: int
        :return: The list with ids of rows of same column.
        :rtype: list(str)

def _get_cells_headers_ids(self, hed, index):
        """
        Returns a list with ids of rows of same column.

        :param hed: The list that represents the table header.
        :type hed: list(list(hatemile.util.html.htmldomelement.HTMLDOMElement))
        :param index: The index of columns.
        :type index: int
        :return: The list with ids of rows of same column.
        :rtype: list(str)
        """
        # pylint: disable=no-self-use

        ids = []
        for row in hed:
            if row[index].get_tag_name() == 'TH':
                ids.append(row[index].get_attribute('id'))
        return ids