           <span class="name deprecated">expires</span>
          <div class="features">@<a href="dart-core/Deprecated-class.html">Deprecated</a>(&#39;Use `message` instead. Will be removed in Dart 3.0.0&#39;)</div>
</section>
        
                        <section class="summary source-code" id="source">
          <h2><span>Implementation</span></h2>
          <pre class="language-dart"><code class="language-dart">@Deprecated(&#39;Use `message` instead. Will be removed in Dart 3.0.0&#39;)
String get exp