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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 _enable_lock(func):
 """ The decorator for ensuring thread-safe when current cache instance is concurrent status. """


    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        self = args[0]
        if self.is_concurrent:
            only_read = kwargs.get('only_read')
            if only_read is None or only_read:
                with self._rwlock:
                    return func(*args, **kwargs)
            else:
                self._rwlock.acquire_writer()
                try:
                    return func(*args, **kwargs)
                finally:
                    self._rwlock.release()
        else:
            return func(*args, **kwargs)

    return wrapper