Is it possible to wrap a flow type in an immutable container? : <p>For example, given the following record:</p>

<pre class="lang-js prettyprint-override"><code>type UserRecord = {
  id: string;
  name: ?string;
  age: number;
}
</code></pre>

<p>Is there some way to do the equivalent of the following:</p>

<pre class="lang-js prettyprint-override"><code>/* @flow */

import { List, Map } from 'immutable'

const users: List&lt;Map&lt;UserRecord&gt;&gt; = List();    
let user: Map&lt;UserRecord&gt;;

user = Map({ id: '666', age: 30 });
users.push(user);
</code></pre>

<p>Otherwise I end up simply using something like <code>Map&lt;string, any&gt;</code> which I think takes away from using Immutable.js with the Flow type system.</p>
