title: Extract an exact key from object in Underscore.js
body: <p>I am using the Underscore.js library. I want to extract an exact key from an object.</p>
  
  <pre><code>var student = {SID : 101; sname: "abc"}
  </code></pre>
  
  <p>I have tried like this.</p>
  
  <pre><code>var key = _.findkey(student, 'SID');
  </code></pre>
  
  <p>But it is showing 'undefined' in the key variable.
  Help me.</p>