code: def sentence2features(self, s):
      return [word2features(s, i, self.template) for i in range(len(s))]
  
file_path: underthesea/underthesea/pipeline/ner/model_crf.py
imports: from os.path import join, dirname
  from underthesea.util.singleton import Singleton
  import pycrfsuite
  import sys
label_desc: Use image node_id 3 for calling the TaggedTransformer obj's underlying member method code with example usage: obj.sentence2features(s) and returns: unknown