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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 close(self):
 """Close the file. Can be called multiple times."""

        if not self.closed:
            # be sure to flush data to disk before closing the file
            self.flush()
            err = _snd.sf_close(self._file)
            self._file = None
            _error_check(err)