NSDictionary with swift : <p><strong>Test dictionary declaration:</strong></p>

<pre><code>var data = [
            "A": [["userid":"1","username":"AAA","usergroupid":"2"], ["userid":"33","username":"ABB","usergroupid":"8"]],
            "B": [["userid":"2","username":"BBB","usergroupid":"8"], ["userid":"43","username":"ABC","usergroupid":"8"]]
           ]
</code></pre>

<p>How do I get the following output ?</p>

<p><strong>For example:</strong> <br/>
 A -> username AAA , ABB<br/>
 B -> username BBB , ABC</p>
