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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_deactivated(self,request,queryset):
 """An admin action for marking several cages as inactive. 		 This action sets the selected cages as Active=False and Death=today. This admin action also shows as the output the number of mice sacrificed."""

        rows_updated = queryset.update(Active=False, End=datetime.date.today() )
        if rows_updated == 1:
            message_bit = "1 cage was"
        else:
            message_bit = "%s cages were" % rows_updated
        self.message_user(request, "%s successfully marked as deactivated." % message_bit)