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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 sync_with_s3(self):
 """ Walk through our self.local_files list, and match them with the list of keys in the S3 bucket. """

        # Create a list to put all the files we're going to update
        self.update_list = []

        # Figure out which files need to be updated and upload all these files
        logger.debug("Comparing {} local files with {} bucket files".format(
            len(self.local_file_list),
            len(self.s3_obj_dict.keys())
        ))
        if self.no_pooling:
            [self.compare_local_file(f) for f in self.local_file_list]
        else:
            cpu_count = multiprocessing.cpu_count()
            logger.debug("Pooling local file comparison on {} CPUs".format(cpu_count))
            pool = ThreadPool(processes=cpu_count)
            pool.map(self.compare_local_file, self.local_file_list)

        logger.debug("Uploading {} new or updated files to bucket".format(len(self.update_list)))
        if self.no_pooling:
            [self.upload_to_s3(*u) for u in self.update_list]
        else:
            logger.debug("Pooling s3 uploads on {} CPUs".format(cpu_count))
            pool = ThreadPool(processes=cpu_count)
            pool.map(self.pooled_upload_to_s3, self.update_list)