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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_archive_part_value(self, part):
 """Return archive part for today"""

        parts_dict = {'year': '%Y',
                      'month': self.month_format,
                      'week': self.week_format,
                      'day': '%d'}
        if self.today is None:
            today = timezone.now()
            if timezone.is_aware(today):
                today = timezone.localtime(today)
            self.today = today
        return self.today.strftime(parts_dict[part])