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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 cast_to_time_qualifier(time_qualifier, timeperiod):
 """ method casts given timeperiod accordingly to time qualifier. For example, will cast session time format of 20100101193412 to 2010010119 with QUALIFIER_HOURLY """


    if time_qualifier == QUALIFIER_HOURLY:
        date_format = SYNERGY_HOURLY_PATTERN
    elif time_qualifier == QUALIFIER_DAILY:
        date_format = SYNERGY_DAILY_PATTERN
    elif time_qualifier == QUALIFIER_MONTHLY:
        date_format = SYNERGY_MONTHLY_PATTERN
    elif time_qualifier == QUALIFIER_YEARLY:
        date_format = SYNERGY_YEARLY_PATTERN
    else:
        raise ValueError('unknown time qualifier: {0}'.format(time_qualifier))

    pattern = define_pattern(timeperiod)
    t = datetime.strptime(timeperiod, pattern)
    return t.strftime(date_format)