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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 set_metric_by_day(self, unique_identifier, metric, date, count, sync_agg=True, update_counter=True):
 """ Sets the count for the ``metric`` for ``unique_identifier``. You must specify a ``date`` for the ``count`` to be set on. Useful for resetting a metric count to 0 or decrementing a metric. The redis backend supports lists for both ``unique_identifier`` and ``metric`` allowing for the setting of multiple metrics for multiple unique_identifiers efficiently. Not all backends may support this. :param unique_identifier: Unique string indetifying the object this metric is for :param metric: A unique name for the metric you want to track :param date: Sets the specified metrics for this date :param count: Sets the sepcified metrics to value of count :param sync_agg: Boolean used to determine if week and month metrics should be updated :param update_counter: Boolean used to determine if overall counter should be updated """

        metric = [metric] if isinstance(metric, basestring) else metric
        unique_identifier = [unique_identifier] if not isinstance(unique_identifier, (types.ListType, types.TupleType, types.GeneratorType,)) else unique_identifier
        results = []
        with self._analytics_backend.map() as conn:
            for uid in unique_identifier:
                hash_key_daily = self._get_daily_metric_key(uid, date)

                for single_metric in metric:
                    daily_metric_name = self._get_daily_metric_name(single_metric, date)

                    if update_counter:  # updates overall counter for metric
                        overall_count = self.get_count(uid, single_metric)
                        day, daily_count = self.get_metric_by_day(uid, single_metric, date, 1)[1].popitem()
                        self._analytics_backend.set(self._prefix + ":" + "analy:%s:count:%s" % (uid, single_metric), overall_count + (count - daily_count))

                    results.append([conn.hset(hash_key_daily, daily_metric_name, count)])

        if sync_agg:
            self.sync_agg_metric(unique_identifier, metric, date, date)

        return results