envy.go
func Get(key string, value string) string {
	gil.RLock()
	defer gil.RUnlock()
	if v, ok := env[key]; ok {
		return v
	}
	return value
}
func Get(key string, value string) string {
	gil.RLock()
	defer gil.RUnlock()
	if v, ok := env[key]; ok {
		return v
	}
	return value
}
// Get a value from the ENV. If it doesn't exist the
// default value will be returned.