code: func (nulls *Nulls) Parse(value interface{}) interface{} {
  	switch nulls.Value.(type) {
  	case Int:
  		return NewInt(value.(int))
  	case Int64:
  		return NewInt64(value.(int64))
  	case UUID:
  		return NewUUID(value.(uuid.UUID))
  	default:
  		return value
  	}
  }
docs: // Parse parses the specified value to the corresponding
  // nullable type. value is one of the inner value hold
  // by a nullable type. i.e int, string, uuid.UUID etc.