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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):
 """ if the MDF was created with memory='minimum' and new channels have been appended, then this must be called just before the object is not used anymore to clean-up the temporary file """

        if self._tempfile is not None:
            self._tempfile.close()
        if self._file is not None and not self._from_filelike:
            self._file.close()