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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 update(self, **kwargs):
 """ Overrides update to concatenate streamed data up to defined length. """

        data = kwargs.get('data')
        if data is not None:
            if (util.pd and isinstance(data, util.pd.DataFrame) and
                list(data.columns) != list(self.data.columns) and self._index):
                data = data.reset_index()
            self.verify(data)
            kwargs['data'] = self._concat(data)
            self._count += 1
        super(Buffer, self).update(**kwargs)