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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, *args, **kwargs):
 """ write close tag of MRV file and close opened file :param force: force closing of externally opened file or buffer """

        if not self.__finalized:
            self._file.write('</cml>')
            self.__finalized = True
        super().close(*args, **kwargs)