jQuery accordion expanded
<p>I am trying to create an accordion with jQuery from this example </p>

<p><a href="http://docs.jquery.com/UI/Accordion" rel="nofollow">http://docs.jquery.com/UI/Accordion</a></p>

<p>The markup is the same, i.e.</p>

<pre><code>&lt;div id="accordion"&gt;
   &lt;h3&gt;&lt;a href="#"&gt;First header&lt;/a&gt;&lt;/h3&gt;
   &lt;div&gt;First content&lt;/div&gt;
   &lt;h3&gt;&lt;a href="#"&gt;Second header&lt;/a&gt;&lt;/h3&gt;
   &lt;div&gt;Second content&lt;/div&gt;
&lt;/div&gt;
</code></pre>

<p>And I have script file enqueued correctly, which has the following content:</p>

<pre><code>$ = jQuery;
$(document).ready(function() {
   $("#accordion").accordion();
});
</code></pre>

<p>But I get this error in the console output</p>

<pre><code>TypeError: 'undefined' is not a function (evaluating '$("#accordion").accordion()')
</code></pre>

<p>The result being all divs are expanded, i.e not clickable.</p>
