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<h3>Choose a Department</h3>
<ul class="list-group">
<li class="list-group-item">
<a data-toggle="collapse" href="#department-cs">Computer Science</a>
<ul class="list-group collapse" id="department-cs">
<h4>Choose a Course</h4>
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<a data-toggle="collapse" href="#course-cs2150">CS2150</a>
<ul class="list-group collapse" id="course-cs2150">
<h4>Choose a Section</h4>
<li class="list-group-item"><a href="#">Section 001</a></li>
<li class="list-group-item"><a href="#">Section 002</a></li>
</ul>
</li>
<li class="list-group-item"><a href="#">CS2110</a></li>
<li class="list-group-item"><a href="#">CS1110</a></li>
</ul>
</li>
<li class="list-group-item">
<a data-toggle="collapse" href="#department-musi">Music</a>
<ul class="list-group collapse" id="department-musi">
<h4>Choose a Course</h4>
<li class="list-group-item"><a href="#">MUSI2350</a></li>
</ul>
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</ul>
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