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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 create(self, client_id, title, unsubscribe_page, confirmed_opt_in, confirmation_success_page, unsubscribe_setting="AllClientLists"):
 """Creates a new list for a client."""

        body = {
            "Title": title,
            "UnsubscribePage": unsubscribe_page,
            "ConfirmedOptIn": confirmed_opt_in,
            "ConfirmationSuccessPage": confirmation_success_page,
            "UnsubscribeSetting": unsubscribe_setting}
        response = self._post("/lists/%s.json" % client_id, json.dumps(body))
        self.list_id = json_to_py(response)
        return self.list_id