title: Differnce between train_test_split and StratifiedShuffleSplit
body: <p>I came across the following statement when trying to find the differnce between <code>train_test_split</code> and <code>StratifiedShuffleSplit</code>.</p>
  <blockquote>
  <p>When <code>stratify</code> is not None train_test_split uses <code>StratifiedShuffleSplit</code> internally,</p>
  </blockquote>
  <p>I was just wondering why the <code>StratifiedShuffleSplit</code> from <code>sklearn.model_selection</code> is used when we can use the <code>stratify</code> argument available in <code>train_test_split</code>.</p>