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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 to_server_timezone(self, timezones, for_year):
 """Returns the Microsoft timezone ID corresponding to this timezone. There may not be a match at all, and there may be multiple matches. If so, we return a random timezone ID. :param timezones: A list of server timezones, as returned by list(account.protocol.get_timezones(return_full_timezone_data=True)) :param for_year: :return: A Microsoft timezone ID, as a string """

        candidates = set()
        for tz_id, tz_name, tz_periods, tz_transitions, tz_transitions_groups in timezones:
            candidate = self.from_server_timezone(tz_periods, tz_transitions, tz_transitions_groups, for_year)
            if candidate == self:
                log.debug('Found exact candidate: %s (%s)', tz_id, tz_name)
                # We prefer this timezone over anything else. Return immediately.
                return tz_id
            # Reduce list based on base bias and standard / daylight bias values
            if candidate.bias != self.bias:
                continue
            if candidate.standard_time is None:
                if self.standard_time is not None:
                    continue
            else:
                if self.standard_time is None:
                    continue
                if candidate.standard_time.bias != self.standard_time.bias:
                    continue
            if candidate.daylight_time is None:
                if self.daylight_time is not None:
                    continue
            else:
                if self.daylight_time is None:
                    continue
                if candidate.daylight_time.bias != self.daylight_time.bias:
                    continue
            log.debug('Found candidate with matching biases: %s (%s)', tz_id, tz_name)
            candidates.add(tz_id)
        if not candidates:
            raise ValueError('No server timezones match this timezone definition')
        if len(candidates) == 1:
            log.info('Could not find an exact timezone match for %s. Selecting the best candidate', self)
        else:
            log.warning('Could not find an exact timezone match for %s. Selecting a random candidate', self)
        return candidates.pop()