data-target</code> to element to automatically assign control of a collapsible element. The <code>data-target</code> attribute accepts a css selector to apply the collapse to. Be sure to add the class <code>collapse</code> to the collapsible element. If you'd like it to default open, add the additional class <code>in</code>.</p>
   <p>To add accordion-like group management to a collapsible control, add the data attribute <code>data-parent="#selector"</code>. Refer to the demo to see this in action.</p>

   