docs: def _to_dict(self):
          """Return a json dictionary representing this model."""
          _dict = {}
          if hasattr(self,
                     'configuration_id') and self.configuration_id is not None:
              _dict['configuration_id'] = self.configuration_id
          if hasattr(self, 'name') and self.name is not None:
              _dict['name'] = self.name
          if hasattr(self, 'created') and self.created is not None:
              _dict['created'] = datetime_to_string(self.created)
          if hasattr(self, 'updated') and self.updated is not None:
              _dict['updated'] = datetime_to_string(self.updated)
          if hasattr(self, 'description') and self.description is not None:
              _dict['description'] = self.description
          if hasattr(self, 'conversions') and self.conversions is not None:
              _dict['conversions'] = self.conversions._to_dict()
          if hasattr(self, 'enrichments') and self.enrichments is not None:
              _dict['enrichments'] = [x._to_dict() for x in self.enrichments]
          if hasattr(self, 'normalizations') and self.normalizations is not None:
              _dict['normalizations'] = [
                  x._to_dict() for x in self.normalizations
              ]
          if hasattr(self, 'source') and self.source is not None:
              _dict['source'] = self.source._to_dict()
          return _dict