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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 aggregate_avg(items, col):
 """ Function to use on Group by Charts. accepts a list and returns the average of the list's items """

    try:
        return aggregate_sum(items, col) / aggregate_count(items, col)
    except Exception:
        log.warning(c.LOGMSG_WAR_DBI_AVG_ZERODIV)
        return 0.0