docs: def _to_dict(self):
          """Return a json dictionary representing this model."""
          _dict = {}
          if hasattr(self, 'function') and self.function is not None:
              _dict['function'] = self.function
          if hasattr(self, 'input_bucket_location'
                    ) and self.input_bucket_location is not None:
              _dict['input_bucket_location'] = self.input_bucket_location
          if hasattr(self,
                     'input_bucket_name') and self.input_bucket_name is not None:
              _dict['input_bucket_name'] = self.input_bucket_name
          if hasattr(self, 'output_bucket_location'
                    ) and self.output_bucket_location is not None:
              _dict['output_bucket_location'] = self.output_bucket_location
          if hasattr(
                  self,
                  'output_bucket_name') and self.output_bucket_name is not None:
              _dict['output_bucket_name'] = self.output_bucket_name
          if hasattr(self, 'batch_id') and self.batch_id is not None:
              _dict['batch_id'] = self.batch_id
          if hasattr(self,
                     'document_counts') and self.document_counts is not None:
              _dict['document_counts'] = self.document_counts._to_dict()
          if hasattr(self, 'status') and self.status is not None:
              _dict['status'] = self.status
          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)
          return _dict