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      <nav aria-label="Table of contents"><h2>Table of contents</h2>
        <ul class="book-toc list-unstyled">
<li><a class="" href="index.html">Foreword</a></li>
<li><a class="" href="welcome.html">Welcome</a></li>
<li class="book-part">Introduction</li>
<li><a class="" href="web-intro.html"><span class="header-section-number">1</span> Shiny and 