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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 mark_sacrificed(self,request,queryset):
 """An admin action for marking several animals as sacrificed. 		 This action sets the selected animals as Alive=False, Death=today and Cause_of_Death as sacrificed. To use other paramters, mice muse be individually marked as sacrificed. This admin action also shows as the output the number of mice sacrificed."""

        rows_updated = queryset.update(Alive=False, Death=datetime.date.today(), Cause_of_Death='Sacrificed')
        if rows_updated == 1:
            message_bit = "1 animal was"
        else:
            message_bit = "%s animals were" % rows_updated
        self.message_user(request, "%s successfully marked as sacrificed." % message_bit)