Golang Telegram Bot

Question

I'm writing a bot on telego, I don't understand how to implement fsm into the bot. Before that, I wrote bots in python aiogram where fsm was built in. How to do it in golang?

package main

import (
    "fmt"
    "os"

    "github.com/mymmrac/telego"
    th "github.com/mymmrac/telego/telegohandler"
    tu "github.com/mymmrac/telego/telegoutil"
)

func main() {
    botToken := os.Getenv("TOKEN")

    // Note: Please keep in mind that default logger may expose sensitive information,
    // use in development only
    bot, err := telego.NewBot(botToken, telego.WithDefaultDebugLogger())
    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }

    // Get updates channel
    updates, _ := bot.UpdatesViaLongPolling(nil)

    // Create bot handler and specify from where to get updates
    bh, _ := th.NewBotHandler(bot, updates)

    // Stop handling updates
    defer bh.Stop()

    // Stop getting updates
    defer bot.StopLongPolling()

    // Register new handler with match on command `/start`
    bh.Handle(func(bot *telego.Bot, update telego.Update) {
        // Send message
        _, _ = bot.SendMessage(tu.Message(
            tu.ID(update.Message.Chat.ID),
            fmt.Sprintf("Hello %s!", update.Message.From.FirstName),
        ))
    }, th.CommandEqual("start"))

    // Register new handler with match on any command
    // Handlers will match only once and in order of registration,
    // so this handler will be called on any command except `/start` command
    bh.Handle(func(bot *telego.Bot, update telego.Update) {
        // Send message
        _, _ = bot.SendMessage(tu.Message(
            tu.ID(update.Message.Chat.ID),
            "Unknown command, use /start",
        ))
    }, th.AnyCommand())

    // Start handling updates
    bh.Start()
}

This code was taken from official documentation https://github.com/mymmrac/telego

I googled and didn't find anything that could help me.