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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 _idx_table_by_num(tables):
 """ Switch tables to index-by-number :param dict tables: Metadata :return list _tables: Metadata """

    logger_jsons.info("enter idx_table_by_num")
    _tables = []
    for name, table in tables.items():
        try:
            # Get the modified table data
            tmp = _idx_col_by_num(table)
            # Append it to the growing calibrated age list of tables
            _tables.append(tmp)
        except Exception as e:
            logger_jsons.error("idx_table_by_num: {}".format(e))
    logger_jsons.info("exit idx_table_by_num")
    return _tables