def METHOD_NAME(self, period):
    timestamp = _now() + _seconds(period)
    fullpath = self.fullpath
    if fullpath.endswith(".lock"):
        fullpath = fullpath[: fullpath.rindex("@")]
    fullpath += "@{}.lock".format(_fmt(timestamp))
    try:
        os.rename(self.fullpath, fullpath)
    except Exception:
        return None
    self.fullpath = fullpath
    return self