WP if social link then display else not display

//if social media link place then display the social icon else not display
	        <div class="ic-follow">
	          <ul>
	           <li>Follow us:</li>
	              <?php

	              	$social_medias= ['facebook','twitter','linkedin','instagram'];
	                foreach ($social_medias as $social_media) {
	                  if (array_key_exists($social_media, $instance) && ($instance[$social_media] != null) ) {
	                    ?>
	                      <li>
	                           <a href="<?php echo $instance[$social_media]; ?>"><?php echo $social_media; ?></a>
	                      </li>
	                    <?php
	                  }
	                }
	             ?>
	          </ul>
	        </div>