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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 _export_model(models):
 """ Switch model tables to index-by-number :param dict models: Metadata :return dict _models: Metadata """

    logger_jsons.info("enter export_model")
    _models = []
    try:
        for name, model in models.items():

            if "summaryTable" in model:
                model["summaryTable"] = _idx_table_by_num(model["summaryTable"])

            # Process ensemble table (special two columns)
            if "ensembleTable" in model:
                model["ensembleTable"] = _idx_table_by_num(model["ensembleTable"])

            if "distributionTable" in model:
                model["distributionTable"] = _idx_table_by_num(model["distributionTable"])

            _models.append(model)

    except Exception as e:
        logger_jsons.error("export_model: {}".format(e))
        print("Error: export_model: {}".format(e))
    logger_jsons.info("exit export_model")
    return _models