get_search_form();ででてくるソース

<?php get_search_form(); ?>

<form role="search" method="get" id="searchform" class="searchform" action="">
  <div>
    <label class="screen-reader-text" for="s">検索:</label>
    <input type="text" value="" name="s" id="s" />
    <input type="submit" id="searchsubmit" value="検索" />
  </div>
</form>   

https://wpdocs.osdn.jp/%E9%96%A2%E6%95%B0%E3%83%AA%E3%83%95%E3%82%A1%E3%83%AC%E3%83%B3%E3%82%B9/get_search_form

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