Set the stepdown window for this instance.

        Date times are assumed to be UTC, so use UTC date times.

        :param datetime.datetime start: The datetime which the stepdown window is to open.
        :param datetime.datetime end: The datetime which the stepdown window is to close.
        :param bool enabled: A boolean indicating whether or not stepdown is to be enabled.
        :param bool scheduled: A boolean indicating whether or not to schedule stepdown.
        :param bool weekly: A boolean indicating whether or not to schedule compaction weekly.

def set_stepdown_window(self, start, end, enabled=True, scheduled=True, weekly=True):
        """Set the stepdown window for this instance.

        Date times are assumed to be UTC, so use UTC date times.

        :param datetime.datetime start: The datetime which the stepdown window is to open.
        :param datetime.datetime end: The datetime which the stepdown window is to close.
        :param bool enabled: A boolean indicating whether or not stepdown is to be enabled.
        :param bool scheduled: A boolean indicating whether or not to schedule stepdown.
        :param bool weekly: A boolean indicating whether or not to schedule compaction weekly.
        """
        # Ensure a logical start and endtime is requested.
        if not start < end:
            raise TypeError('Parameter "start" must occur earlier in time than "end".')

        # Ensure specified window is less than a week in length.
        week_delta = datetime.timedelta(days=7)
        if not ((end - start) <= week_delta):
            raise TypeError('Stepdown windows can not be longer than 1 week in length.')

        url = self._service_url + 'stepdown/'
        data = {
            'start': int(start.strftime('%s')),
            'end': int(end.strftime('%s')),
            'enabled': enabled,
            'scheduled': scheduled,
            'weekly': weekly,
        }

        response = requests.post(
            url,
            data=json.dumps(data),
            **self._instances._default_request_kwargs
        )
        return response.json()