How can I use library object?

I have an error.
Document is struct object on goquery library.
I can't use it in my code below. How can I do?

package main
import (
	"log"
	"github.com/PuerkitoBio/goquery"
	"os"
)

func getLocalFile(filename string) (*Document) { // Error
	f, e := os.Open(FILTER_FILE)
	if e != nil {
		log.Fatal(e)
	}
	defer f.Close()

	doc, e := goquery.NewDocumentFromReader(f)
	if e != nil {
		log.Fatal(e)
	}
	return doc
}

const FILE_NAME = "input.html"
func main() {
	doc := getLocalFile(FILE_NAME)
	println(doc)
}

> The Go Programming Language Specification
>
> Qualified identifiers
>
> A qualified identifier is an identifier qualified with a package name
> prefix. Both the package name and the identifier must not be blank.
>
> QualifiedIdent = PackageName "." identifier .
>
> A qualified identifier accesses an identifier in a different package,
> which must be imported. The identifier must be exported and declared
> in the package block of that package.
>
> math.Sin // denotes the Sin function in package math

Use the fully qualified name: goquery.Document. For example,

package main

import (
	"github.com/PuerkitoBio/goquery"
	"log"
	"os"
)

func getLocalFile(filename string) *goquery.Document {
	f, e := os.Open(filename)
	if e != nil {
		log.Fatal(e)
	}
	defer f.Close()

	doc, e := goquery.NewDocumentFromReader(f)
	if e != nil {
		log.Fatal(e)
	}
	return doc
}

const FILE_NAME = "input.html"

func main() {
	doc := getLocalFile(FILE_NAME)
	println(doc)
}