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    In this section
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        <h2 class="au-sidenav__title"><a href="#">Animals</a></h2>
        <ul class="au-link-list">
            <li><a href="#">Mammals</a></li>
            <li><a href="#">Reptiles</a></li>
            <li><a href="#">Insects</a></li>
            <li><a href="#">Dinosaurs</a>
                <ul class="au-link-list">
                    <li><a href="#">Ornithischia</a></li>
                    <li><a href="#">Sauropodomorpha </a></li>
                    <li><a href="#">Theropods</a>
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                            <li><a href="#" class="active">Tyrannosaurus</a></li>
                            <li><a href="#">Massospondylus</a></li>
                            <li><a href="#">Baryonyx</a></li>
                        </ul>
                    </li>
                </ul>
            </li>
            <li><a href="#">Birds</a></li>
        </ul>
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