code: def sentence2labels(self, s):
      return [row[-1] for row in s]
  
file_path: underthesea/underthesea/pipeline/chunking/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 4 for calling the TaggedTransformer obj's underlying member method code with example usage: obj.sentence2labels(s) and returns: unknown