code: func (obj *Field) GetNxProperties(ctx context.Context) (*NxFieldProperties, error) {
  	result := &struct {
  		Properties *NxFieldProperties	`json:"qProperties"`
  	} {}
  	err := obj.rpc(ctx, "GetNxProperties", result)
  	return result.Properties, err 
  }
docs: // Gets the properties of a field.
  // 
  // The property OneAndOnlyOne is set to true if one and only value has been selected in the field prior setting the property.