def METHOD_NAME():
    """
    Update our metadata list of sampling dates.
    """
    dates = sorted(set([obj.date for obj in CountyMortgageData.objects.all()]))
    date_list = ["{}".format(date) for date in dates]
    date_list_obj, cr = MortgageMetaData.objects.get_or_create(
        name="sampling_dates"
    )
    date_list_obj.json_value = date_list
    date_list_obj.save()
    logger.info(
        "Sampling dates updated; the {} dates now range from {} to {}".format(
            len(date_list), date_list[0], date_list[-1]
        )
    )