code: func remapEnv(mapping map[string]string) {
  	for k, v := range mapping {
  		currentVal := os.Getenv(k)
  		newVal := os.Getenv(v)
  		if currentVal == "" && newVal != "" {
  			os.Setenv(k, newVal)
  		}
  	}
  }
docs: // copies environment variables to new names without overwriting existing values