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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 save(self, data, fname, header=None):
 """ Save data on fname. :param data: numpy array or list of lists :param fname: path name :param header: header to use """

        write_csv(fname, data, self.sep, self.fmt, header)
        self.fnames.add(getattr(fname, 'name', fname))