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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 report(self) -> None: """ Finish and report to the log. """

        while self._stack:
            self.stop(self._stack[-1])
        now = get_now_utc_pendulum()
        grand_total = datetime.timedelta()
        overall_duration = now - self._overallstart
        for name, duration in self._totaldurations.items():
            grand_total += duration

        log.info("Timing summary:")
        summaries = []
        for name, duration in self._totaldurations.items():
            n = self._count[name]
            total_sec = duration.total_seconds()
            mean = total_sec / n if n > 0 else None

            summaries.append({
                'total': total_sec,
                'description': (
                    "- {}: {:.3f} s ({:.2f}%, n={}, mean={:.3f}s)".format(
                        name,
                        total_sec,
                        (100 * total_sec / grand_total.total_seconds()),
                        n,
                        mean)),
            })
        summaries.sort(key=lambda x: x['total'], reverse=True)
        for s in summaries:
            # noinspection PyTypeChecker
            log.info(s["description"])
        if not self._totaldurations:
            log.info("<no timings recorded>")

        unmetered = overall_duration - grand_total
        log.info(
            "Unmetered time: {:.3f} s ({:.2f}%)",
            unmetered.total_seconds(),
            100 * unmetered.total_seconds() / overall_duration.total_seconds()
        )
        log.info("Total time: {:.3f} s", grand_total.total_seconds())