class_docstr: Tokenizer transform abstract class.
docstr: Extra checks for Subword options.
docstr_tok: ["Extra","checks","for","Subword","options","."]
code: def _validate_options(cls, opts):
      """Extra checks for Subword options."""
      assert (
          0 <= opts.src_subword_alpha <= 1
      ), "src_subword_alpha should be in the range [0, 1]"
      assert (
          0 <= opts.tgt_subword_alpha <= 1
      ), "tgt_subword_alpha should be in the range [0, 1]"
  
imports: import re
  from onmt.utils.logging import logger
  from onmt.transforms import register_transform
  from .transform import Transform, ObservableStats
  from onmt.constants import DefaultTokens
label_desc: Use image node_id 3 for calling the TokenizerTransform obj's underlying member method code with example usage: obj._validate_options(cls, opts) without return types