code: def _asdict(self):
      if self.constituency is None:
          return {"sentiment": self.sentiment, "text": self.text}
      else:
          return {
              "sentiment": self.sentiment,
              "text": self.text,
              "constituency": str(self.constituency),
          }
  
imports: import collections
  from collections import namedtuple
  import logging
  import json
  import random
  import re
  from typing import List
  from stanza.models.classifiers.utils import WVType
  from stanza.models.common.vocab import PAD, PAD_ID, UNK, UNK_ID
  import stanza.models.constituency.tree_reader
label_desc: Use image node_id 4 for calling the SentimentDatum obj's underlying member method code with example usage: obj._asdict() and returns: dict, dict