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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 _flush(self):
 """Save the contents of data to the file on disk. You should not need to call this manually."""

        d = os.path.dirname(self.path)
        if not os.path.isdir(d):
            os.makedirs(d)
        with io.open(self.path, 'w', encoding='utf8') as f:
            yaml.safe_dump(self._data, f, default_flow_style=False, encoding=None)