class_docstr: Base class for all the templates.
  Most of methods are abstract, with some exceptions to hold the common methods for all template, such as ``loss_ids``, ``save``, ``load``.
  
  Args:
      tokenizer (:obj:`PreTrainedTokenizer`): A tokenizer to appoint the vocabulary and the tokenization strategy.
      placeholder_mapping (:obj:`dict`): A place holder to represent the original input text.
class_docstr_tok: ["Base","class","for","all","the","templates",".","Most","of","methods","are","abstract",",","with","some","exceptions","to","hold","the","common","methods","for","all","template",",","such","as","``","loss_ids","``",",","``","save","``",",","``","load","``",".","Args",":","tokenizer","(",":","obj",":","`","PreTrainedTokenizer","`",")",":","A","tokenizer","to","appoint","the","vocabulary","and","the","tokenization","strategy",".","placeholder_mapping","(",":","obj",":","`","dict","`",")",":","A","place","holder","to","represent","the","original","input","text","."]
docstr: check whether the template format is correct.
  TODO: add more
docstr_tok: ["check","whether","the","template","format","is","correct",".","TODO",":","add","more"]
code: def _check_template_format(
      self,
  ):
      r"""check whether the template format is correct.
      TODO: add more
      """
      mask_num = 0
      for i, d in enumerate(self.text):
          if "mask" in d:
              mask_num += 1
  
      if mask_num == 0:
          raise RuntimeError(
              f"'mask' position not found in the template: {self.text}. Please Check!"
          )
  
imports: from abc import abstractmethod
  from typing import *
  import paddle
  from data_utils import InputExample
label_desc: Use image node_id 6 for calling the ErnieManualTemplate obj's underlying member method code with example usage: obj._check_template_format() without return types