title: Racket list results if no index element is present
body: <p>I am trying to modify this program in Racket such that if no index element is present in this list, it should return <code>#f</code>. A little guidance is helpful.
  Thanks in advance</p>
  
  <pre><code>#lang racket
  (define get-nth
    (lambda (index lst)
      (let loop ((index index) (my-list lst))
        (cond ((null? my-list) lst)
              ((= index 0) (car my-list))
              (else (loop (- index 1) (cdr my-list)))))))
  
  (get-nth 4 '(a b))
  </code></pre>
  
  <p><code>;#f</code></p>