dataSource.swift

struct SectionOfBooks {
    var header: String?
    var items: [Book]
}

func createDataSource() -> RxTableViewSectionedAnimatedDataSource<SectionOfBooks> {
    return RxTableViewSectionedAnimatedDataSource(
        configureCell:{ (ds, tableView, indexPath, book) in
            let cell = tableView.dequeueReusableCell(...)
            cell.textLabel?.text = book.title
            return cell
        }
    )
}