Go에서 영구 환경 변수를 어떻게 설정하나요?

<code class="go">import "github.com/spf13/viper"

// LoadConfig loads the configuration file and sets the environment variables.
func LoadConfig(configFile string) error {
    viper.SetConfigFile(configFile)
    if err := viper.ReadInConfig(); err != nil {
        return err
    }

    // Retrieve the environment variables from the configuration file.
    for key, value := range viper.AllSettings() {
        if err := os.Setenv(key, value); err != nil {
            return err
        }
    }

    return nil
}</code>