code: def to_dict(self):
          
          obj = {
              'id' : self.identifier,
              'name' : self.name,
              'description' : self.description,
              'type' : self.data_type.to_dict()
          }
          if not self.default is None:
              obj['default'] = self.default
          return obj
docs: Convert attribute definition into a dictionary.
  
          Returns
          -------
          dict
              Json-like dictionary representation of the attribute definition