## Exercise

<div class="exercise">
<p>Copy the <code>example3.py</code> app to <code>exercise.py</code> and 
implement a route to compute the GCD of two integers given in the URL. </p>
<p>Python's <code>math</code> module has a GCD function. </p>
<p>For example, the GCD(15,20) is 5. </p>
<p>Hints:</p>
<ul>
    <li>to have *two* arguments, 
</ul>
</div>