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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 reindex_axis(self, new_index, axis, method=None, limit=None, fill_value=None, copy=True):
 """ Conform block manager to new index. """

        new_index = ensure_index(new_index)
        new_index, indexer = self.axes[axis].reindex(new_index, method=method,
                                                     limit=limit)

        return self.reindex_indexer(new_index, indexer, axis=axis,
                                    fill_value=fill_value, copy=copy)