class_docstr: Convert between text-label and text-index
  Args:
      config: config from yaml file
class_docstr_tok: ["Convert","between","text-label","and","text-index","Args",":","config",":","config","from","yaml","file"]
code: def add_special_char(self, dict_character):
      dict_character = ["blank"] + dict_character
      return dict_character
  
file_path: PaddleHub/modules/image/text_recognition/ch_pp-ocrv3/character.py
imports: import string
  import numpy
label_desc: Use image node_id 2 for calling the CharacterOps obj's underlying member method code with example usage: obj.add_special_char(dict_character) and returns: dict_character