Why (or how) does a Keras model skip Stemming or Lemmatization steps?

This \[Keras article / tutorial here\]\[1\] does perform text standardization i.e removing HTML elements, punctuation, etc. from the text dataset, however, there is a distinct lack of any stemming or lemmatization before the vectorization step.

I have a bit of experience in deep learning but I am very new to NLP, and I just got to know (from a \[different tutorial on Udemy\]\[2\], which BTW was using Bag of Words) that using either a Stemmer or a Lemmatizer helps in …

datascience keras lemmatization stemming