title: call function after some time but only one time
body: <p>I want to call function in javascript only a one time but after some time.</p>
  
  <pre><code>setTimeout(function(){ $('.alert').fadeOut(2000) }, 5000);
  </code></pre>
  
  <p>right now i am using this, But this function call multiple time. I need to call only a single time after some time</p>