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>   

Internal error - WordPress Codex 日本語版

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