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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 revert(self, request, queryset):
 """ Admin action to revert a configuration back to the selected value """

        if queryset.count() != 1:
            self.message_user(request, _("Please select a single configuration to revert to."))
            return

        target = queryset[0]
        target.id = None
        self.save_model(request, target, None, False)
        self.message_user(request, _("Reverted configuration."))

        return HttpResponseRedirect(
            reverse(
                'admin:{}_{}_change'.format(
                    self.model._meta.app_label,
                    self.model._meta.model_name,
                ),
                args=(target.id,),
            )
        )