title: Get info from json
body: <p>My node application is generation an error in format:</p>
  
  <pre><code>{ [Error: Username already exists]
    index: 0,
    instance:
     { username: [Getter/Setter],
       name: [Getter/Setter],
       email: [Getter/Setter],
       password: [Getter/Setter],
       birthday: [Getter/Setter],
       gender: [Getter/Setter],
       join_date: [Getter/Setter],
       id: [Getter/Setter] } }
  </code></pre>
  
  <p>How can i access the "Username already exists" text? The output above its a console.log() of the object.</p>
  
  <p>Thank you</p>