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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 dedupe(self):
 """ Performs the deduplication and its preliminary checks. """

        if len(self.pool) == 1:
            logger.debug("Ignore set: only one message found.")
            self.stats['mail_unique'] += 1
            self.stats['set_ignored'] += 1
            return

        try:
            # Fine-grained checks on mail differences.
            self.check_differences()
            # Call the deduplication strategy.
            self.apply_strategy()
        except UnicodeDecodeError as expt:
            self.stats['set_rejected_encoding'] += 1
            logger.warning(
                "Reject set: unparseable mails due to bad encoding.")
            logger.debug(str(expt))
        except SizeDiffAboveThreshold:
            self.stats['set_rejected_size'] += 1
            logger.warning("Reject set: mails are too dissimilar in size.")
        except ContentDiffAboveThreshold:
            self.stats['set_rejected_content'] += 1
            logger.warning("Reject set: mails are too dissimilar in content.")
        else:
            # Count duplicate sets without deletion as skipped.
            if not self.stats['mail_deleted']:
                logger.info("Skip set: no deletion happened.")
                self.stats['set_skipped'] += 1
            else:
                self.stats['set_deduplicated'] += 1