title: How to find "num_words" or vocabulary size of Keras tokenizer when one is not assigned?
body: <p>So if I were to not pass <code>num_words</code> argument when initializing <code>Tokenizer()</code>, how do I find the vocabulary size after it is used to tokenize the training dataset?</p>
  
  <p>Why this way, I don't want to limit the tokenizer vocabulary size to know how well my Keras model perform without it. But then I need to pass on this vocabulary size as the argument in the model's first layer definition.</p>