Go: Example of WaitGroup

	var wg sync.WaitGroup
	for i, file := range dir {
		wg.Add(1)
		go func(i int, file os.DirEntry) {
			defer wg.Done()
			fileEntropies, err := readFile(fileName + "/" + file.Name())
			if err != nil {
				panic(err)
			}
			entropiies[i] = fileEntropies
		}(i, file)
	}


	wg.Wait()