check not null for list in a list at specific index : <p>How do I access <code>list2</code> in <code>list1</code> below and check <code>IsnotNull</code> in an Assert </p>

<pre><code>List&lt;Object&gt; list1= new List&lt;Object&gt;();

List&lt;int&gt; list2= new List&lt;int&gt;();

list1.add(someValue);
list1.add(list2);

Assert.IsNotNull(list1[1]..??);
</code></pre>
