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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 lock(self, timeout=10):
 """ Advisory lock. Use to ensure that only one LocalSyncClient is working on the Target at the same time. """

        logger.debug("Locking %s", self.lock_file)
        if not os.path.exists(self.lock_file):
            self.ensure_path(self.lock_file)
            with open(self.lock_file, "w"):
                os.utime(self.lock_file)
        self._lock.acquire(timeout=timeout)