to csc format.
        index, columns : Index, optional
            Row and column labels to use for the resulting DataFrame.
            Defaults to a RangeIndex.

        Returns
        -------
        DataFrame
            Each column of the DataFrame is stored as a
            :class:`arrays.SparseArray`.

        Examples
        --------
        >>> import scipy.sparse
        >>> mat = scipy.sparse.eye(3)
        >>> pd.DataFrame.sparse.from_spmatrix(mat)
             0    1    2
        0  1.0  0.0  0.0
        1  0.0  1.0  0.0
        2  0.0  0.0  1.0
        r