如何在Go中地道地将DataBase访问转换为函数

import (
    "database/sql"
    _ "github.com/go-sql-driver/mysql"
)

func createConnection() (*sql.DB, error) {
    db, err := sql.Open("mysql", "username:password@tcp(hostname:port)/database")
    if err != nil {
        return nil, err
    }
    return db, nil
}

func getUserByID(userID int) (User, error) {
    db, err := createConnection()
    if err != nil {
        return User{}, err
    }
    defer db.Close()

    var user User
    err = db.QueryRow("SELECT id, name, email FROM users WHERE id = ?", userID).Scan(&user.ID, &user.Name, &user.Email)
    if err != nil {
        return User{}, err
    }

    return user, nil
}

func main() {
    user, err := getUserByID(1)
    if err != nil {
        fmt.Println("Error:", err)
        return
    }

    fmt.Println("User:", user)
}