How to use the @gooddata/typings.AFM.isAttributeFilter function in @gooddata/typings

export function isAttributeFilter(filter: AFM.FilterItem): filter is AFM.AttributeFilterItem {
    return AFM.isAttributeFilter(filter);
}

private sanitizeFilter(filter: AFM.CompatibilityFilter): ExecuteAFM.CompatibilityFilter | null {
        if (AFM.isAttributeFilter(filter)) {
            return convertAttributeFilter(filter);
        } else if (AFM.isAbsoluteDateFilter(filter)) {
            return convertAbsoluteDateFilter(filter);
        } else if (AFM.isRelativeDateFilter(filter)) {
            return convertRelativeDateFilter(filter);
        }
        return filter;
    }
}