Update tokenizer internal vocabulary based on a list of texts or list of sequences.
fit_text_tokenizer(object, x, ...)Tokenizer returned by text_tokenizer()
Vector/list of strings, or a generator of strings (for memory-efficiency); Alternatively a list of "sequence" (a sequence is a list of integer word indices).
Unused
Other text tokenization: sequences_to_matrix,
  text_tokenizer,
  texts_to_matrix,
  texts_to_sequences_generator,
  texts_to_sequences