You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: main.go
    path of file: ./repos/watcher/example/close_watcher
    
    the code of the file until where you have to start completion: package main

import (
	"fmt"
	"log"
	"time"

	"
    
func main() {
	w := watcher.New()

	go func() {
		for {
			select {
			case event := <-w.Event:
				fmt.Println(event)
			case err := <-w.Error:
				log.Fatalln(err)
			case <-w.Closed:
				return
			}
		}
	}()

	// Watch test_folder for changes.
	if err := w.Add("../test_folder"); err != nil {
		log.Fatalln(err)
	}

	// Print a list of all of the files and folders currently
	// being watched and their paths.
	for path, f := range w.WatchedFiles() {
		fmt.Printf("%s: %s\n", path, f.Name())
	}

	fmt.Println()

	// Close the watcher after watcher started.
	go func() {
		w.Wait()
		w.Close()
	}()

	// Start the watching process - it'll check for changes every 100ms.
	if err := w.Start(time.Millisecond * 100); err != nil {
		log.Fatalln(err)
	}

	fmt.Println("watcher closed")
}