class_docstr: Transformation that simulate typos error to transform sentence.
  
      https://arxiv.org/pdf/1711.02173.pdf
code: def _get_typo_method(self):
      if self._mode == "replace":
          return _replace_cn
      elif self._mode == "swap":
          return swap
  
      else:
          return random.choice([_replace_cn, swap])
  
file_path: textflint/textflint/generation/transformation/NERCN/ent_typos.py
imports: from ....common.utils.word_op import *
  from ..transformation import Transformation
  from ....common.utils.list_op import trade_off_sub_words
  from textflint.generation.transformation.UTCN import CnHomophones
label_desc: Use image node_id 7 for calling the EntTypos obj's underlying member method code with example usage: obj._get_typo_method() and returns: _replace_cn, swap, random