div class="aside aside-parameter">
    <p class="aside-title">Parameter</p>
    <p>Parameter function: the function that needs to run only once</p>

</div>

<div class="aside aside-returns">
    <p class="aside-title">Returns</p>
    <p>the function result</p>

</div>

                      </div>
                      <div class="declaration">
                        <h4>Declaration</h4>
                        <div class="language">
                          <p class="aside-title">Swift</p>
              