goroutine usage


`go` keyword가 async같이  `<-` await
```typepackage mainimport (	"fmt"	"time")func f(from string) {	for i := 0; i < 3; i++ {		fmt.Println(from, ":", i)	}}func main() {	f("direct")	go f("goroutine")	go func(msg string) {		fmt.Println(msg)	}("going")	fmt.Println("done")	time.Sleep(time.Second)}```
> [The await/async concurrency pattern in Golang](https://madeddu.xyz/posts/go-async-await/)





