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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_active(self):
 """ Get all of the active messages ordered by the active_datetime. """

        now = timezone.now()
        return self.select_related().filter(active_datetime__lte=now,
                                              inactive_datetime__gte=now).order_by('active_datetime')