How Can I Use Go's 'compress/gzip' Package for Efficient File Compression and Decompression?

import (
    "bytes"
    "compress/gzip"
    "io"
    "os"
)

func compressFile(sourceFile, compressedFile string) error {
    input, err := os.ReadFile(sourceFile)
    if err != nil {
        return err
    }

    var b bytes.Buffer
    w := gzip.NewWriter(&b)
    if _, err := w.Write(input); err != nil {
        return err
    }
    if err := w.Close(); err != nil {
        return err
    }

    if err := os.WriteFile(compressedFile, b.Bytes(), 0644); err != nil {
        return err
    }

    return nil
}

func readCompressedFile(compressedFile string) error {
    f, err := os.Open(compressedFile)
    if err != nil {
        return err
    }
    defer f.Close()

    r, err := gzip.NewReader(f)
    if err != nil {
        return err
    }
    defer r.Close()

    if _, err := io.Copy(os.Stdout, r); err != nil {
        return err
    }

    return nil
}