envy.go
func MustGet(key string) (string, error) {
	gil.RLock()
	defer gil.RUnlock()
	if v, ok := env[key]; ok {
		return v, nil
	}
	return "", fmt.Errorf("could not find ENV var with %s", key)
}
func MustGet(key string) (string, error) {
	gil.RLock()
	defer gil.RUnlock()
	if v, ok := env[key]; ok {
		return v, nil
	}
	return "", fmt.Errorf("could not find ENV var with %s", key)
}
// Get a value from the ENV. If it doesn't exist
// an error will be returned