title: How to convert this json to Flutter Object
body: <p>I want to convert this json to object.My problem is in sub key "rates".please help me.</p>
  
  <pre><code>{
    "info": "Exchange Rates",
    "timestamp": "1558080000",
    "rates": {
      "USD": "1,536.7",
      "VND": "6.5693",
      "PHP": "29.184",
      "KRW": "128.60",
      "HKD": "195.77",
      "BRL": "379.62",
      "RSD": "14.557",
      "MYR": "367.94"
    }
  }
  </code></pre>