code: def validate_value(self, value):
          
          super(ValuesListField, self).validate_value(value)
  
          if value is not None:
              if value not in self.selection_to_id_map:
                  raise ValidationError(
                      self.record,
                      'Field "{}" invalid value "{}". Valid options: {}'.format(
                          self.name,
                          value,
                          ', '.join(self.selection_to_id_map.keys())
                      )
                  )
docs: Validate provided value is one of the valid options