def save(self, filename=None):
        filename = Path(filename) if filename is not None else self.filename
        with filename.open("w") as f:
            f.write(self.yaml)
def __init__(self, queue, level, formatter):
        super(QueueingLogHandler, self).__init__()
        self._queue = queue
        self.setLevel(level)
        self.setFormatter(formatter)