How do you extract a value out of a golang map[string] string thats typed with interface{} : <p>I have something like this:</p>

<pre><code>x1 := someFunctionWithAnInterfaceReturnValue()
</code></pre>

<p>and the underlying type is something like this: </p>

<pre><code>x2 := map[string] string{"hello": "world"}
</code></pre>

<p>How would I access value in x1?</p>

<p>Essentially I want the equivalent of this for x1:</p>

<pre><code> var value string = x2["hello"]
</code></pre>
