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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, car_id=None, wake_if_asleep=False, force=False):
 """Update all vehicle attributes in the cache. This command will connect to the Tesla API and first update the list of online vehicles assuming no attempt for at least the [update_interval]. It will then update all the cached values for cars that are awake assuming no update has occurred for at least the [update_interval]. Args: inst (Controller):
 The instance of a controller car_id (string):
 The vehicle to update. If None, all cars are updated. wake_if_asleep (bool):
 Keyword arg to force a vehicle awake. This is processed by the wake_up decorator. force (bool):
 Keyword arg to force a vehicle update regardless of the update_interval Returns: True if any update succeeded for any vehicle else false Throws: RetryLimitError """

        cur_time = time.time()
        with self.__lock:
            #  Update the online cars using get_vehicles()
            last_update = self._last_attempted_update_time
            if (force or cur_time - last_update > self.update_interval):
                cars = self.get_vehicles()
                for car in cars:
                    self.car_online[car['id']] = (car['state'] == 'online')
                self._last_attempted_update_time = cur_time
            # Only update online vehicles that haven't been updated recently
            # The throttling is per car's last succesful update
            # Note: This separate check is because there may be individual cars
            # to update.
            update_succeeded = False
            for id_, value in self.car_online.items():
                # If specific car_id provided, only update match
                if (car_id is not None and car_id != id_):
                    continue
                if (value and  # pylint: disable=too-many-boolean-expressions
                        (id_ in self.__update and self.__update[id_]) and
                        (force or id_ not in self._last_update_time or
                         ((cur_time - self._last_update_time[id_]) >
                          self.update_interval))):
                    # Only update cars with update flag on
                    try:
                        data = self.get(id_, 'data', wake_if_asleep)
                    except TeslaException:
                        data = None
                    if data and data['response']:
                        response = data['response']
                        self.__climate[car_id] = response['climate_state']
                        self.__charging[car_id] = response['charge_state']
                        self.__state[car_id] = response['vehicle_state']
                        self.__driving[car_id] = response['drive_state']
                        self.__gui[car_id] = response['gui_settings']
                        self.car_online[car_id] = (response['state']
                                                   == 'online')
                        self._last_update_time[car_id] = time.time()
                        update_succeeded = True
            return update_succeeded