class_docstr: TextStats contains following basic information:
code: def tfidf(self):
      return self._tfidf
  
imports: from typing import Dict, Optional, Tuple
  from xai.data.abstract_stats import AbstractStats
  from xai.data.constants import STATSKEY
  from xai.data.exceptions import InvalidTypeError, InvalidSizeError
label_desc: Use image node_id 14 for calling the TextStats obj's underlying member method code with example usage: obj.tfidf() and returns: self