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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _render_rows(self):
 """ Render the rows in the current stylesheet """

        _datas = getattr(self, '_datas', ())
        headers = getattr(self, 'headers', ())
        for index, row in enumerate(_datas):
            row_number = index + 2
            for col_num, value in enumerate(row):
                cell = self.worksheet.cell(row=row_number, column=col_num + 1)
                if value is not None:
                    cell.value = value
                else:
                    cell.value = ""
                if len(headers) > col_num:
                    header = headers[col_num]
                    format = get_cell_format(header)
                    if format is not None:
                        cell.number_format = format