<button class="btn btn-primary" type="button" data-toggle="modal" data-target="#attendance_problems" id="open_attendance_problems" style="display:none"></button>
<div class="modal fade" id="attendance_problems" tabindex="-1" role="dialog" aria-labelledby="exampleModalLabel" aria-hidden="true">
    <div class="modal-dialog" role="document" style="max-width: 70%">
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