code: func (a *DatetimePickerAction) MarshalJSON() ([]byte, error) {
  	return json.Marshal(&struct {
  		Type    ActionType `json:"type"`
  		Label   string     `json:"label,omitempty"`
  		Data    string     `json:"data"`
  		Mode    string     `json:"mode"`
  		Initial string     `json:"initial,omitempty"`
  		Max     string     `json:"max,omitempty"`
  		Min     string     `json:"min,omitempty"`
  	}{
  		Type:    ActionTypeDatetimePicker,
  		Label:   a.Label,
  		Data:    a.Data,
  		Mode:    a.Mode,
  		Initial: a.Initial,
  		Max:     a.Max,
  		Min:     a.Min,
  	})
  }
docs: // MarshalJSON method of DatetimePickerAction