zero/string.go
func (s String) MarshalText() ([]byte, error) {
	if !s.Valid {
		return []byte{}, nil
	}
	return []byte(s.String), nil
}
func (s String) MarshalText() ([]byte, error) {
	if !s.Valid {
		return []byte{}, nil
	}
	return []byte(s.String), nil
}
// MarshalText implements encoding.TextMarshaler.
// It will encode a blank string when this String is null.