def METHOD_NAME(self):
    path = Path(self.path)
    regex = re.compile(str(self.regex_filter)) if self.regex_filter else None
    # For better control of imported tasks, file reading has been changed to ascending order of filenames.
    # In other words, the task IDs are sorted by filename order.
    for file in sorted(path.rglob('*'), key=os.path.basename):
        if file.is_file():
            key = file.name
            if regex and not regex.match(key):
                logger.debug(key + ' is skipped by regex filter')
                continue
            yield str(file)