在Golang中如何将punycode转换为unicode？

I wanna convert url f.e.:

xn--h1aaebtrh5b.xn--p1ai --> кисточки.рф

And of course reverse:

kremlin.ru ---> xn--d1abbgf6aiiy.xn--p1ai

I try use idna package, but i can't import vendor package idna

Link on doc: https://godoc.org/golang.org/x/net/idna#Profile.ToUnicode

Try import:

import "golang_org/x/net/idna"

Get error:

main.go:18:8: cannot find package "golang_org/x/net/idna" in any of:
    /usr/local/go/src/golang_org/x/net/idna (from $GOROOT)
    /home/arseny/go/src/golang_org/x/net/idna (from $GOPATH)

Another try:

import "vendor/golang_org/x/net/idna"

Errors:

main.go:18:8: must be imported as golang_org/x/net/idna

main.go:19:2: use of vendored package not allowed

Some people say that this code work

In bash:

go get golang.org/x/net/idna

Example code go:

package main

import (
    "fmt"
    "golang.org/x/net/idna"
)

var p *idna.Profile

func main() {
    // Raw Punycode has no restrictions and does no mappings.
    p = idna.New()
    fmt.Println(p.ToUnicode("xn--d1abbgf6aiiy.xn--p1ai"))
}

But i'm still hope that another way exist. I unlike to do local copy of package into $GOROOT path.