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<li class="chapter" data-level="" data-path="index.html"><a href="index.html"><i class="fa fa-check"></i>Preface</a>
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<li class="chapter" data-level="0.1" data-path="index.html"><a href="index.html#why-does-this-book-exist"><i class="fa fa-check"></i><b>0.1</b> Why does this book exist?</a></li>
<li class="chapter" data-level="0.2" data-path="index.html"><a href="index.html#the-golden-age-of-data"><i class="fa fa-check"></i><b>0.2</b> The golden age of data</a></li>
<li class="chapter" dat