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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 update(self, title, unsubscribe_page, confirmed_opt_in, confirmation_success_page, unsubscribe_setting="AllClientLists", add_unsubscribes_to_supp_list=False, scrub_active_with_supp_list=False):
 """Updates this list."""

        body = {
            "Title": title,
            "UnsubscribePage": unsubscribe_page,
            "ConfirmedOptIn": confirmed_opt_in,
            "ConfirmationSuccessPage": confirmation_success_page,
            "UnsubscribeSetting": unsubscribe_setting,
            "AddUnsubscribesToSuppList": add_unsubscribes_to_supp_list,
            "ScrubActiveWithSuppList": scrub_active_with_supp_list}
        response = self._put("/lists/%s.json" % self.list_id, json.dumps(body))