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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 backup_db(self):
 """ " Generate a xxxxx.backup.json. """

        with self.db_mutex:
            if os.path.exists(self.json_db_path):
                try:
                    shutil.copy2(self.json_db_path, self.backup_json_db_path)
                except (IOError, OSError):
                    _logger.debug("*** No file to copy.")