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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 get_all_regions(db_connection):
 """ Gets a list of all regions. :return: A list of all regions. Results have regionID and regionName. :rtype: list """


    if not hasattr(get_all_regions, '_results'):
        sql = 'CALL get_all_regions();'
        results = execute_sql(sql, db_connection)
        get_all_regions._results = results

    return get_all_regions._results