title: How to create Recoil MutableSnapshot?
body: <p>According to the Docs,
  <a href="https://recoiljs.org/docs/api-reference/core/RecoilRoot" rel="nofollow noreferrer">https://recoiljs.org/docs/api-reference/core/RecoilRoot</a></p>
  <p><code>&lt;RecoilRoot&gt;</code> accept props as <code>initializeState?: (MutableSnapshot =&gt; void)</code> signature.<br />
  That able to initialize Recoil State so I want to use this props but I don't understand how to make <code>MutableSnapshot</code> object.</p>
  <pre><code>import {RecoilRoot} from 'recoil';
  
  function AppRoot() {
    return (
      &lt;RecoilRoot initializeState={/* How to setup arguments here? */} &gt;
        &lt;ComponentThatUsesRecoil /&gt;
      &lt;/RecoilRoot&gt;
    );
  }
  </code></pre>
  <p>On the other hand <code>Snapshot</code> is easier to get from <code>useRecoilSnapshot()</code> though.</p>