How to use the pingouin.utils._export_table function in pingouin

# ---------------------------------------------------------------------
    # Append parametric columns
    stats.loc[:, 'Parametric'] = parametric

    # Reorder and drop empty columns
    stats = stats[np.array(col_order)[np.isin(col_order, stats.columns)]]
    stats = stats.dropna(how='all', axis=1)

    # Rename Time columns
    if (contrast in ['multiple_within', 'multiple_between', 'within_between']
       and interaction):
        stats['Time'].fillna('-', inplace=True)
        stats.rename(columns={'Time': factors[0]}, inplace=True)

    if export_filename is not None:
        _export_table(stats, export_filename)
    return stats

# Standardize correlation coefficients (Fisher z-transformation)
    stats['z'] = np.round(np.arctanh(stats['r'].values), 3)

    col_order = ['X', 'Y', 'method', 'tail', 'n', 'outliers', 'r', 'CI95%',
                 'r2', 'adj_r2', 'z', 'p-unc', 'p-corr', 'p-adjust',
                 'BF10', 'power']

    # Reorder columns and remove empty ones
    stats = stats.reindex(columns=col_order).dropna(how='all', axis=1)

    # Add covariates names if present
    if covar is not None:
        stats.insert(loc=3, column='covar', value=str(covar))

    if export_filename is not None:
        _export_table(stats, export_filename)
    return stats