Comment lancer de manière asynchrone un navigateur après l'initialisation du serveur dans Go ?

import (
    "fmt"
    "log"
    "net"
    "net/http"

    "github.com/julienschmidt/httprouter"
)

func main() {
    r := httprouter.New()
    r.GET("/test", func(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
        fmt.Fprint(w, "Welcome!\n")
    })

    // Open the listening socket
    l, err := net.Listen("tcp", "localhost:3000")
    if err != nil {
        log.Fatal(err)
    }

    // Start the browser after the listening socket is open
    err = open.Start("http://localhost:3000/test")
    if err != nil {
        log.Println(err)
    }

    // Begin the blocking server loop
    log.Fatal(http.Serve(l, r))
}