title: How can I convert an NSDictionary to an NSMutableDictionary?
body: <p>I have an existing NSDictionary that has:</p>
  
  <pre><code>{
      "charts_count" = 2;
      "created_at" = "2010-04-12T16:37:32Z";
      exchange = NASDAQ;
      "followers_count" = 259;
      id = 8404;
      industry = "&lt;null&gt;";
      "messages_count" = 1436;
      ric = "GRPN.O";
      sector = "&lt;null&gt;";
      symbol = GRPN;
      title = Groupon;
      "updated_at" = "2011-09-05T04:17:56Z";
  }
  </code></pre>
  
  <p>How can I take these contents and put it into a new NSMutableDictionary? </p>