code: def build_token_char_map(tokens):
      """Builds a map that maps arbitrary tokens to arbitrarily chosen characters.
      This is required to overcome the limitations of SentencePiece.
  
      Arguments
      ---------
      tokens: list
          a list of tokens for which to produce the map
  
      Returns
      -------
      token_map: dict
          a dictionary with original tokens as keys and
          new mappings as values
      """
      chars = char_range("A", "Z") + char_range("a", "z")
      values = list(filter(lambda chr: chr != " ", tokens))
      token_map = dict(zip(values, chars[: len(values)]))
      token_map[" "] = " "
      return token_map
  
imports: from functools import reduce
  from speechbrain.wordemb.util import expand_to_chars
  import speechbrain
  import torch
  import re
label_desc: Use image node_id 13 for calling a global function with example usage: build_token_char_map(tokens) and returns: token_map