code: def get_tokenized_sequences(
      dataset: tf.data.Dataset,
      tokenizer: tftext.Tokenizer = tftext.WhitespaceTokenizer(),
      input_key: str = "sentence",
  ) -> Iterable[Sequence[bytes]]:
      """Returns tokenized sequences for vocabulary building."""
      dataset = dataset.map(
          lambda example: tokenizer.tokenize(example[input_key]),
          num_parallel_calls=tf.data.experimental.AUTOTUNE,
      )
      yield from tfds.as_numpy(dataset)
  
imports: import time
  from typing import Iterable, Sequence
  from absl import logging
  import tensorflow
  import tensorflow_datasets
  import tensorflow_text
  import vocabulary
label_desc: Use image node_id 1 for calling a global function with example usage: get_tokenized_sequences(dataset, tokenizer, input_key) without return types