How to define own struct on substrate ink

1. I want to know how to define own struct.
2. I referred Substrate ink! Sample,but I could not find it.

I write sample code as following. https://realtakahashi-work.medium.com/substrate-ink-how-to-define-own-struct-%E7%8B%AC%E8%87%AA%E6%A7%8B%E9%80%A0%E4%BD%93%E3%81%AE%E5%AE%A3%E8%A8%80%E6%96%B9%E6%B3%95-8f4893089ba4