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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_anniversary_periods(start, finish, anniversary=1):
 """ Return a list of anniversaries periods between start and finish. """

    import sys
    current = start
    periods = []
    while current <= finish:
        (period_start, period_finish) = date_period(DATE_FREQUENCY_MONTHLY, anniversary, current)
        current = period_start + relativedelta(months=+1)
        period_start = period_start if period_start > start else start
        period_finish = period_finish if period_finish < finish else finish
        periods.append((period_start, period_finish))
    return periods