docstr: Get the number of characters in the charset
  
  this is equal to the maximum possible label.
  
  Returns
  -------
      number of characters in the charset
docstr_tok: ["Get","the","number","of","characters","in","the","charset","this","is","equal","to","the","maximum","possible","label",".","Returns","--","--","--","-","number","of","characters","in","the","charset"]
code: def size(self):
      """Get the number of characters in the charset
  
      this is equal to the maximum possible label.
  
      Returns
      -------
          number of characters in the charset
      """
      return len(self.charset)
  
file_path: calamari/calamari_ocr/ocr/dataset/codec.py
imports: from dataclasses import dataclass, field
  from typing import List, TYPE_CHECKING, Iterator, Set
  from paiargparse import pai_dataclass, pai_meta
  from tfaip.util.multiprocessing.parallelmap import tqdm_wrapper
  from tfaip.data.pipeline.definitions import PipelineMode
  from calamari_ocr.utils import glob_all
label_desc: Use image node_id 5 for calling the Codec obj's underlying member method code with example usage: obj.size() and returns: len