code: def token_list_width(tokenlist):
      
      ZeroWidthEscape = Token.ZeroWidthEscape
      return sum(get_cwidth(c) for item in tokenlist for c in item[1] if item[0] != ZeroWidthEscape)
docs: Return the character width of this token list.
      (Take double width characters into account.)
  
      :param tokenlist: List of (token, text) or (token, text, mouse_handler)
                        tuples.