code: def _remove_non_korean_characters(self, tokens):
      new_tokens = [
          token for token in tokens if token in self.VALID_CHARS
      ]
      return new_tokens
  
imports: import logging
  import re
  import warnings
  from pathlib import Path
  from typing import Iterable, List, Optional, Union
  import g2p_en
  import jamo
  from packaging.version import parse
  from typeguard import check_argument_types
  from espnet2.text.abs_tokenizer import AbsTokenizer
label_desc: Use image node_id 3 for calling the Jaso obj's underlying member method code with example usage: obj._remove_non_korean_characters(tokens) and returns: new_tokens